Lily's error is in the first step, (2+i)^2 ≠ 4 + i^2.
(2+i)^2 = (2+i)(2+i) and you need to FOIL.
(2+i)^2 = (2+i)(2+i)
= 4 + 2i + 2i + i^2
= 4 + 4i + (-1)
= 3 + 4i
Bonus:
If you want to multipy (2+i) by (a+bi) and not end up with a complex number, you'd first FOIL
(2+i)(a+bi) = 2a + 2bi + ai + bi^2
We know i^2 = -1, so this becomes
= 2a + 2bi + ai + b(-1)
= 2a + 2bi + ai - b
= 2a - b + 2bi + ai
Now, for this not to be complex, we need the imaginary pieces to cancel each other out. In other words 2bi+ai=0. For that to happen, 2b + a = 0, or
2b = -a or a = -2b
So it would seem that if we pick any b-value and make a = -2b, then we'll end up with a non-complex number.
Let's try b=5, making a = -10
(2+i)(-10+5i) = -20 + 10i - 10i + 5i^2
The 10i's cancel and 5i^2 = -5, so we're left just with -25.
A boat heading out to sea starts out at Point A, at a horizontal distance of 1035 feet from a lighthouse/the shore. From that point, the boat’s crew measures the angle of elevation to the lighthouse’s beacon-light from that point to be 8 degrees At some later time, the crew measures the angle of elevation from point B to be 5 degrees . Find the distance from point A to point B. Round your answer to the nearest foot if necessary.
Answer: Let's assume that the distance between the lighthouse and point B is x. Then, we can use the tangent function to set up an equation involving the angles of elevation:
tan(8°) = (height of lighthouse) / (distance from A to lighthouse)
tan(5°) = (height of lighthouse) / x
Since the height of the lighthouse is the same in both equations, we can set them equal to each other:
tan(8°) = tan(5°) * (distance from A to lighthouse) / x
Solving for x:
x = (tan(5°) * 1035) / tan(8°)
x ≈ 14416
So the distance from point A to point B is approximately 14,416 feet.
Step-by-step explanation:
Three times a number lies between negative three and six in digits
Answer:
-3 ≤ 3x ≤ 6
To solve for "x", we can divide each part of the inequality by 3:
-1 ≤ x ≤ 2
Therefore, the number "x" must lie between -1 and 2 in order to satisfy the condition in the sentence.
Step-by-step explanation:
Let n be a positive integer. If (1+2+3+4+5+6)^2 = 1^3+2^3+. N^3, what is the value of n?
PLEASE HELP :|
The value of n is 3, n is a positive integer
We know that:
1 + 2 + 3 + 4 + 5 + 6 = 21
Therefore:
(1 + 2 + 3 + 4 + 5 + 6)² = 21² = 441
Now, let's look at the sum of cubes:
1³ + 2³ + ... + n³ = (1 + 2 + ... + n)²
We already know that 1 + 2 + ... + 6 = 21, so we can rewrite the equation as:
1³ + 2³ + ... + n³ = (1 + 2 + ... + n)²
1³ + 2³ + ... + n³ = (1 + 2 + 3 + 4 + 5 + 6 + ... + n)²
We want to find the value of n that makes this equation true. We know that the sum of the first n positive integers is:
1 + 2 + 3 + ... + n = n(n+1)/2
So we can rewrite the equation as:
1³ + 2³ + ... + n³ = [n(n+1)/2]²
Now we substitute the value we know for 1 + 2 + 3 + 4 + 5 + 6:
441 = [6(7)/2]²
441 = 21²
So n(n+1)/2 = 7, which means:
n(n+1) = 14
The only positive integer solution for n in this case is 3, because:
n(n+1) = 14
n² + n - 14 = 0
(n-3)(n+4) = 0
The positive integer solution is n = 3, which means:
1³ + 2³ + 3³ = [3(4)/2]² = 36² = 441
So the value of n is 3.
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The zeros of a function are the values of
for which the function is equal to zero. Enter a number in each blank to make true statements about the function ()=(2−6)(−4)
1) m(x) = 0 when x = 3, and when x = 4.
2) The graph of m intercepts the x-axis at x = 3, and x = 4.
3) The zeros of m are 3 and 4.
1) m(x) = 0 when x = 3, and when x = 4.
To find the zeros of m(x), we set the function equal to zero and solve for x:
m(x) = 0
(2x - 6)(x - 4) = 0
This equation is equal to zero when either 2x - 6 = 0 or x - 4 = 0.
Solving 2x - 6 = 0 gives x = 3, and solving x - 4 = 0 gives x = 4.
2) The graph of m intercepts the x-axis at x = 3, and x = 4.
The x-intercepts of a function are the points where the graph intersects the x-axis, or where y = 0. So, we can find the x-intercepts of m(x) by setting y = m(x) = 0:
m(x) = 0
(2x - 6)(x - 4) = 0
This equation is equal to zero when either 2x - 6 = 0 or x - 4 = 0.
So, the x-intercepts of m(x) are (3, 0) and (4, 0).
3) The zeros of m are 3 and 4.
The zeros of a function are the values of x for which the function is equal to zero. So, the zeros of m(x) are x = 3 and x = 4.
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The given question is incomplete, the complete question is:
The zeros of a function are the values of x for which the function is equal to zero.
Enter a number in each blank to make true statements about the function m(x)=(2x−6)(x−4).
1)m(x) = 0 when x =__, and when x =___
2) the graph of m intercept the x axis at x = __, and x =___ .
3) zeros of m are ___ and ____?
The sum of the first 18 terms of the series -100 + 122 - 148. 84 + 181. 5848–… is
1) 1569. 77
2) -1569. 77
3) -15840. 45
4) 15840. 45
The sum of the first 18 terms of the series -100 + 122 - 148. 84 + 181. 5848–… is option (C) -15840.45
To find the sum of the first 18 terms of the given series, we need to first identify the pattern in the series.
The given series is: -100 + 122 - 148.84 + 181.5848 - ...
We can observe that each term is obtained by multiplying the previous term by -1.22 and then adding a constant. In other words, if the nth term is represented by Tn, then:
Tn = (-1.22) × T(n-1) + C
where C is a constant.
To find the constant C, we can use the first term of the series, which is -100:
-100 = (-1.22) × T(0) + C
where T(0) represents the 0th term of the series, which is not given. However, we can find T(0) by dividing the first term by (-1.22):
T(0) = -100 / (-1.22) = 81.9672
Substituting this value of T(0) in the above equation, we get:
-100 = (-1.22) × 81.9672 + C
C = 100 + 1.22 × 81.9672 = 200.2046
Therefore, the nth term of the series can be represented as:
Tn = (-1.22) × T(n-1) + 200.2046
Using this formula, we can find the sum of the first 18 terms of the series as follows:
S18 = T1 + T2 + T3 + ... + T18
= -100 + 122 - 148.84 + 181.5848 - ... + (-1)^17 × T(17)
= -100 + 122 - 148.84 + 181.5848 - ... + (-1)^17 × (-1.22)^17 × T(0) + (-1)^17 × 200.2046
= -100 + 122 - 148.84 + 181.5848 - ... - 1.3579774 × 10^8 + 200.2046
= -15840.45
Therefore, the correct option is (3) -15840. 45
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Solve System of Equations from Context (Graphically)Taylor and her children went into a movie theater and she bought $81 worth of bags of popcorn and candies. Each bag of popcorn costs $9 and each candy costs $4.50. She bought 6 more candies than bags of popcorn. Graphically solve a system of equations in order to determine the number of bags of popcorn, x,x, and the number of candies, y,y, that Taylor bought.
Therefore , the solution of the given problem of equation comes out to be Taylor purchased 3 bags of popcorn and 9 candies.
What is equation?The use of the same variable word in mathematical formulas frequently ensures agreement between two assertions. Mathematical equations, also referred to as assertions, are used to demonstrate expression the equality of many academic figures. Instead of dividing 12 into 2 parts in this instance, the normalise technique adds b + 6 to use the sample of y + 6 instead.
Here,
Let's describe our variables first:
x is the quantity of popcorn bags bought, and y is the quantity of sweets bought.
The following system of equations can be constructed using the information provided:
The price of the packages of popcorn and candies is $81, or
=> 9x + 4.5y.
=> y = x + 6 (Taylor purchased 6 more candies than bags of popcorn)
The first step in solving this system of equations numerically is to rewrite the first equation in slope-intercept notation as follows:
=> 4.5y = -9x + 81
=> y = (-2)x + 18
Let's plot the y-intercept at (0,6) and then locate another point by moving up 1 unit and to the right 1 unit to graph the second equation, y = x + 6. This demonstrates our argument (1,7).
The two lines now meet at the number (3,9), indicating that Taylor purchased 3 bags of popcorn and 9 candies.
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at which points on the graph of inverse of f(x)=1/(x^2+1) + (1-2x)^(1/3), x>=0 the tangents of f(x) and its inverse are perpendicular?
The pοint οn the graph οf [tex]\mathrm {f^{(-1)}}[/tex] where the tangent οf f(x) and [tex]\mathrm {f^{(-1)}}[/tex](x) are perpendicular is apprοximately (0.71, 0.42).
What is the graph?A graph is a visual representatiοn οf data that shοws the relatiοnship between different variables οr sets οf data. Graphs are used tο display and analyze data in a way that makes it easier tο understand patterns, trends, and relatiοnships.
Tο find the pοints οn the graph οf the inverse functiοn where the tangents οf f(x) and its inverse are perpendicular, we need tο use the fact that the prοduct οf slοpe οf twο perpendicular lines is -1.
Let y = f(x) = 1/(x²+1) + (1-2x[tex])^{(1/3)[/tex], x >= 0
We want tο find the pοints οn the graph οf [tex]\mathrm {f^{(-1)}}[/tex] where the tangent οf f(x) and [tex]\mathrm {f^{(-1)}}[/tex] (x) are perpendicular. Let (a, b) be a pοint οn the graph οf f^(-1) such that [tex]\mathrm {f^{(-1)}}[/tex] (a) = b.
The slοpe οf the tangent tο f(x) at x = [tex]\mathrm {f^{(-1)}}[/tex] (a) is 1/f' [tex]\mathrm {f^{(-1)}}[/tex] (a)).
f'(x) = -2x/(x²+1)² - (1-2x[tex])^{(-2/3)[/tex] / (3 * (1-2x[tex])^{(2/3)[/tex])
[tex]\mathrm {f^{(-1)}}[/tex] (a) = b implies a = f(b).
Therefοre, the slοpe οf the tangent tο [tex]\mathrm {f^{(-1)}}[/tex] at b is f' [tex]\mathrm {f^{(-1)}}[/tex] (a)).
Sο, we need tο find a pοint (a, b) οn the graph οf [tex]\mathrm {f^{(-1)}}[/tex] such that:
1/f' [tex]\mathrm {f^{(-1)}}[/tex] (a)) * f' [tex]\mathrm {f^{(-1)}}[/tex] (a)) = -1
Simplifying, we get:
-2 [tex]\mathrm {f^{(-1)}}[/tex] (a)/ [tex]\mathrm {f^{(-1)}}[/tex] a)² + 1)² - (1-2 [tex]\mathrm {f^{(-1)}}[/tex] (a)[tex])^{(-2/3)[/tex] / (3 * (1-2 [tex]\mathrm {f^{(-1)}}[/tex] (a)[tex])^{(2/3)[/tex]) = -1
Simplifying further, we get:
2 [tex]\mathrm {f^{(-1)}}[/tex] (a)/ [tex]\mathrm {f^{(-1)}}[/tex] (a)² + 1)² + (1-2 [tex]\mathrm {f^{(-1)}}[/tex] (a)[tex])^{(-2/3)[/tex] / (3 * (1-2 [tex]\mathrm {f^{(-1)}}[/tex] (a)[tex])^{(2/3)[/tex]) = 1
Let y = [tex]\mathrm {f^{(-1)}}[/tex] (x), then x = f(y).
Substituting x = a and y = b, we get:
a = f(b)
2b/(b²+1)² + (1-2b[tex])^{(-2/3)[/tex] / (3 * (1-2b[tex])^{(2/3)[/tex]) = 1
This equatiοn cannοt be sοlved analytically, sο we need tο use numerical methοds tο apprοximate the sοlutiοn.
Using a graphing calculatοr οr sοftware, we can plοt the graphs οf f(x) and [tex]\mathrm {f^{(-1)}}[/tex] (x) and find the pοints where the tangents are perpendicular. One such pοint is (0.71, 0.42) (rοunded tο twο decimal places).
Therefοre, the pοint οn the graph οf [tex]\mathrm {f^{(-1)}}[/tex] where the tangent οf f(x) and [tex]\mathrm {f^{(-1)}}[/tex] (x) are perpendicular is apprοximately (0.71, 0.42).
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The 3 lines x = 3, y – 2. 5 =-(x – 0. 5), and y – 2,5 = x – 3. 5 intersect at point P.
Find the coordinates of P. Verify algebraically that the lines all intersect at P.
All three equations are satisfied when x = 3 and y = 2, which means that the lines intersect at the point (3, 2).
To find the coordinates of point P where the three lines intersect, we need to solve the system of equations formed by the three lines:
x = 3 (equation 1)
y - 2.5 = -(x - 0.5) (equation 2)
y - 2.5 = x - 3.5 (equation 3)
From equation 1, we know that x = 3. substituting this into equations 2 and 3, we get:
y - 2.5 = -2.5 (from equation 2)
y - 2.5 = -0.5 (from equation 3)
Simplifying these equations, we get:
y = 0 (from equation 2)
y = 2 (from equation 3)
So the coordinates of point P are (3, 2).
To verify that the lines all intersect at this point, we can substitute these coordinates into each of the original equations and check that they hold:
For equation 1: x = 3 holds when x = 3.
For equation 2: y - 2.5 = -(x - 0.5) becomes y - 2.5 = -(3 - 0.5) = -2 holds when x = 3 and y = 2.
For equation 3: y - 2.5 = x - 3.5 becomes y - 2.5 = 3 - 3.5 = -0.5 holds when x = 3 and y = 2.
So all three equations are satisfied when x = 3 and y = 2, which means that the lines intersect at the point (3, 2).
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Which of the following is an example of a function with a domain (-∞ + ∞ )and a range (-∞,+ ∞)?
A. f(x)-(2x)10
B. f(x)-(2x)
C. f(x)=(2x)/4
D. f(x)-(2x)/2
Option A is an example of a function with a domain (-∞, +∞) and a range (-∞, +∞). We can check this by verifying that there are no restrictions on the domain and that the function can output any real number.
What is a domain?The domain of a function in mathematics is the collection of all potential input values (also known as the independent variable) for which the function is specified. It is the collection of all x-values that can be inserted into a function to generate a valid output.
In the given question, for any value of x, the expression [tex](2x)^10[/tex] will result in a real number, since any real number raised to an even power will have a positive result. Therefore, there are no restrictions on the domain.
Similarly, since any real number raised to an even power is positive, multiplying [tex](2x)^10[/tex] by -2 will also result in a real number, which means that the function can output any real number. Therefore, the range is also (-∞, +∞).
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The Great African Elephant Census, completed in 2016, found a total population of about 350,000 African ele- phants, and concluded that the population was decreasing at a rate of about 8% per year, primarily due to poaching. What is the approximate half-life for the population? Based on this approximate half-life and assuming that the rate of decline holds steady, about how many African elephants will remain in the year 2050?
The solution of the given problem of percentage comes out to be In 2050, there will be about 153,000 African elephants left.
What does a percentage actually mean?In statistics, a "a%" is a figure or statistic that is expressed as a percentage of 100. The words "pct," "pct," but instead "pc" are also not frequently used. However, the sign "%" is frequently used to represent it. The percentage sum is flat; there are no dimensions. Percentages are truly integers because their numerator almost always equals 100. Either the % symbol (%) or the additional term "fraction" must come before a number to denote that it is a percentage.
Here,
We can apply the exponential decay formula if we presume that this rate of decline stays constant:
=> [tex]N(t) = N0 * (1/2)^(t/T)[/tex]
The half-life, T, is a problem we want to address. Since we are aware that the population is declining by 8% annually:
=> [tex](1/2)^{(1/T)} = 0.92[/tex]
Using both sides' natural logarithms:
=> [tex]ln[(1/2)^{(1/T)}] = ln(0.92) (0.92)[/tex]
=> (1/T) * ln(1/2) Equals ln (0.92)
=> 1/T Equals ln(0.92) / ln(1/2)
=> 8.6 years T
This indicates that the number of African elephants is predicted to decrease by half every 8.6 years.
=> 2050 - 2016 = 34 years
There will be roughly 3.95 half-lives between 2016 and 2050 because the population halves every 8.6 years.
Consequently, the population in 2050 will be roughly:
=> N(2050)=N0*(1/2)*(3.95)=350,000*(0.5)*(3.95)=153,000 elephants
Consequently, if the rate of decrease remains constant, we can calculate that there
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Find the area under the standard normal curve to the left of z =-2.77 and to the right of z--2.22. Round your answer to four decimal places. if necessary. Answer Tables Keypad If you would like to look up the value in a table, select the table you want to view, then either click the cell at the intersection of the row and column or use the arrow keys to find the appropriate cell in the table and select it using the Space key Normal Table-" to-z Normal Table-a to z
The area under the standard normal curve to the left of z=-2.77 and to the right of z=-2.22 is 0.0167-0.0033 = 0.0134. This answer is rounded to four decimal places, so the answer is 0.0134.
What is area?Area is a two-dimensional measurement, defined as the amount of two-dimensional space taken up by a shape or object. It is measured in units such as square meters, square kilometers, or square feet.
The area under the standard normal curve to the left of z=-2.77 and to the right of z=-2.22 can be calculated using the normal tables. The normal table shows the area under the standard normal curve from 0 up to the given z-value. Using the normal table, the area to the left of z=-2.77 is 0.0033 and the area to the right of z=-2.22 is 0.0167.
The normal table is a useful tool for calculating the area under the standard normal curve for different z-values. The table is organized such that the row headers are the z-values and the column headers are the area under the curve from 0 up to the given z-value. By looking up the z-values in the table, we can calculate the area under the standard normal curve for any given area. This makes it easy to calculate the area under the standard normal curve for any given set of z-values.
Using a standard normal table, the area to the left of z = -2.77 is 0.0028 (rounded to four decimal places), and the area to the right of z = -2.22 is 0.0139 (rounded to four decimal places).
Therefore, the area under the standard normal curve to the left of z = -2.77 and to the right of z = -2.22 is:
0.0028 + 0.0139 = 0.0167 (rounded to four decimal places)
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Need help with these problems
1) A nonagon is a polygon with nine sides.
To find the sum of the interior angles of a nonagon, we can use the formula:
aggregate of interior angles = (n - 2) × 180°
where n stands for the number of sides of the polygon.
Substituting n = 9 for a nonagon, we get:
sum of interior angles = (9 - 2) × 180° = 7 × 180°
Thus, the aggregate of the interior angles of a nonagon is:
sum of interior angles = 1260°
2)
To find the sum of the interior angles of a 17-gon, we can use the formula:
aggregate of interior angles = (n - 2) × 180°
where n stands for the number of sides of the polygon.
Substituting n = 17 for a 17-gon, we get:
sum of interior angles = (17 - 2) × 180° = 15 × 180°
Thus, the aggregate of the interior angles of a 17-gon is:
sum of interior angles = 2700°
3)
It is correct to state that a hexagon can be defined as a polygon with six sides.
To find the sum of the interior angles of a hexagon, we can use the formula:
aggregate of interior angles = (n - 2) × 180°
where n refers to the number of sides of the polygon.
Replacing n = 6 for a hexagon, we get:
sum of interior angles = (6 - 2) × 180° = 4 × 180°
Therefore, the sum of the interior angles of a hexagon is:
sum of interior angles = 720°
4)
To find the sum of the interior angles of a regular 20-gon, we can use the formula:
aggregate of interior angles = (n - 2) × 180°
where n refers to the number of sides of the polygon.
Substituting n = 20 for a 20-gon, we get:
sum of interior angles = (20 - 2) × 180 degrees = 18 × 180°
Thus, the sum of the interior angles of a regular 20-gon is:
sum of interior angles = 3,240°
5)
A regular octagon is a polygon with eight sides that are all congruent and eight angles that are all congruent.
To find the measure of each exterior angle of a regular octagon, we can use the formula:
dimensions of each exterior angle = 360° ÷ number of sides
For a regular octagon, the number of sides is 8. Replacing this value into the formula, we get:
measure of each exterior angle = 360° ÷ 8
Simplifying this expression, we get:
the dimensions of each exterior angle = 45°
Therefore, the dimensions of each exterior angle of a regular octagon is 45°.
6)
A regular 24-gon is a polygon with 24 sides that are all congruent and 24 angles that are all congruent.
To find the measure of each exterior angle of a regular 24-gon, we can use the formula:
mensuration of each exterior angle = 360° ÷ number of sides
For a regular 24-gon, the number of sides is 24. Replacing this value into the formula, we get:
measure of each exterior angle = 360° ÷ 24
Simplifying this expression, we get:
The measure of each exterior angle = 15°
Therefore, the measure of each exterior angle of a regular 24-gon is 15°
7)
The sum of the interior angles of any pentagon can be calculated using the formula:
Aggregate of interior angles = (n - 2) × 180°
where n refers the number of sides of the polygon.
For a pentagon, n = 5, so we have:
Aggregate of interior angles = (5 - 2) × 180° = 3 × 180° = 540°.
We can use this fact to set up an equation using the given expressions for the interior angles:
(5x + 2) + (7x - 11) + (13x - 31) + (8x - 19) + (10x - 3) = 540
Simplifying and solving for x, we get:
43x - 62 = 540
43x = 602
x = 14
Therefore, x = 14.
8)
The sum of the exterior angles of any polygon is always 360 degrees. Therefore, we can add the six exterior angles of the hexagon to get:
(11x-30) + 5x + 50 + (2x+60) + (6x-10) + 50 = 360
Simplifying and solving for x, we get:
24x + 120 = 360
24x = 240
x = 10
Therefore, x = 10.
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Use point-slope form to write the equation of a line that passes through the point
(
−
15
,
−
3
)
(−15,−3) with slope
−
3
7
−
7
3
.
In response to the query, we can state that Therefore, the equation of the line that passes through the point (-15,-3) with slope[tex]-3/7 - 7/3 is 12x + 7y = -201.[/tex]
What is equation?An equation is a mathematical statement that proves the equality of two expressions connected by an equal sign '='. For instance, 2x – 5 = 13. Expressions include 2x-5 and 13. '=' is the character that links the two expressions. A mathematical formula that has two algebraic expressions on either side of an equal sign (=) is known as an equation. It depicts the equivalency relationship between the left and right formulas. L.H.S. = R.H.S. (left side = right side) in any formula.
The point-slope form of the equation of a line is given by:
y - y1 = m(x - x1)
where (x1, y1) is a point on the line and m is the slope of the line.
[tex]y - (-3) = (-3/7 - 7/3)(x - (-15))\\y + 3 = (-36/21)(x + 15)\\y + 3 = (-12/7)(x + 15)\\7y + 21 = -12x - 180\\12x + 7y = -201[/tex]
Therefore, the equation of the line that passes through the point (-15,-3) with slope[tex]-3/7 - 7/3 is 12x + 7y = -201.[/tex]
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PLS HELP ASAP MARKING BRAINLEIST
Answer: 21
Step-by-step explanation: The 8 is equivilent to the unknown number (a) therefore the answer is all of the numbers added and u would get 21
Answer:
22.4
Step-by-step explanation:
To find the missing side length:
[tex]a^{2}[/tex] + [tex]b^{2}[/tex] = [tex]c^{2}[/tex]
[tex]8^{2}[/tex] + [tex]5^{2}[/tex] = [tex]c^{2}[/tex]
64 + 25 = [tex]c^{2}[/tex]
89 = [tex]c^{2}[/tex]
[tex]\sqrt{89}[/tex] = [tex]\sqrt{c^{2} }[/tex]
9.4 ≈ c
Perimeter is the distance around the triangle, so we add the sides
8 + 5 + 9.4 = 22.4
Helping in the name of Jesus.
from the top of a building, a man observes a car moving toward him. as the car moves 100 ft closer, the angle of depression changes from 15 to 33 o o . find the height of the building.
When a man on top of a building sees a car approaching him and as the car moves 100 ft closer, the angle of depression changes from 15 to 33 degrees, the height of the building is 159.8 feet.
To solve the problem, we can use the tangent function. Let x be the distance between the man and the building, then we have:
tan(15) = h / x ...........(1) and tan(33) = h / (x - 100) ...........(2)
Dividing (2) by (1), we get:
tan(33) / tan(15) = (x - 100) / x
Simplifying the expression, we have:
(x - 100) / x = 2.22
Solving for x, we get:
x = 100 / 1.22 ≈ 81.97
Using equation (1), we can solve for the height of the building:
h = x * tan(15)
h ≈ 159.8
Therefore, the height of the building is approximately 159.8 feet.
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In a voter survey (February 2022), the Center Party had 5.2% sympathizers out of 1972 people interviewed. In a corresponding survey in January 2022, 6.0% of 2189 interviewees sympathized with the Center Party.
Form a 95% confidence interval for the difference in the proportion of Center Party members at the two survey times.
Answer only with the statistical margin of error and enter this as a number between 0 and 1 to 3 correct decimal places.
0.0247
To form a 95% confidence interval for the difference in the proportion of Center Party members at the two survey times, one needs to use the following formula: CI = (p1 - p2) ± z (SE), where p1 and p2 are the sample proportions for February 2022 and January 2022, respectively. To calculate the standard error (SE), use the following formula: SE = √ [(p1 (1-p1))/n1 + (p2 (1-p2))/n2], where n1 and n2 are the sample sizes for February 2022 and January 2022, respectively.The statistical margin of error is the term used to describe the range of error that is expected for a statistical estimate or survey. This range of error is expressed as a percentage of the estimate or survey result, and it is typically denoted as a plus or minus sign before the percentage value. Thus, the statistical margin of error can be calculated by taking the product of the standard error and the z-score corresponding to the desired level of confidence. In this case, the level of confidence is 95%, and the corresponding z-score is 1.96. Therefore, the formula for the margin of error is: ME = z × SE, where z = 1.96. So, let's now calculate the confidence interval for the difference in the proportion of Center Party members at the two survey times.CI = (p1 - p2) ± z (SE)CI = (0.052 - 0.06) ± 1.96 (SE)SE = √ [(p1 (1-p1))/n1 + (p2 (1-p2))/n2]SE = √ [(0.052 (1-0.052))/1972 + (0.06 (1-0.06))/2189]SE = 0.0126ME = z × SE = 1.96 × 0.0126ME = 0.0247Therefore, the 95% confidence interval for the difference in the proportion of Center Party members at the two survey times is (-0.057, -0.029), and the statistical margin of error is 0.0247 (rounded to 4 decimal places).Answer: 0.0247
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Then lengths of the sides of a square are 9 meters. Find the length of the of the diagonal of the square.
? square root of ?
Answer:
12.73 meters
Step-by-step explanation:
Let d be the length of the diagonal, and let s be the length of each side of the square. Then, we have:
d^2 = s^2 + s^2 (by the Pythagorean theorem)
d^2 = 2s^2
d = sqrt(2s^2) = sqrt(2) * s
Substituting s = 9 meters, we get:
d = sqrt(2) * s = sqrt(2) * 9 meters
d ≈ 12.73 meters
Therefore, the length of the diagonal of the square is approximately 12.73 meters
In
△
O
P
Q
,
△OPQ,
Q
O
‾
≅
P
Q
‾
QO
≅
PQ
and
m
∠
Q
=
5
0
∘
.
m∠Q=50
∘
. Find
m
∠
P
.
m∠P
The angle m∠P is equal to 50 degrees.
Since triangle OPQ is isosceles with PQ congruent to QO, we know that angle OPQ is congruent to angle OQP. Let's call this angle x. Then, we can set up an equation based on the fact that the angles in a triangle add up to 180 degrees: x + x + 50 = 180
Simplifying the equation, we get
2x + 50 = 180
Subtracting 50 from both sides, we get
2x = 130
Dividing by 2, we get:
x = 65
Therefore, angle OPQ and angle OQP are both equal to 65 degrees. Since angle OPQ and angle P are supplementary (they add up to 180 degrees), we can find angle P as:
m∠P = 180 - m∠OPQ
=> 180 - 2x
=> 180 - 2(65)
=> 50 degrees.
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Kim has 1. 04 pounds of meat. She uses 0. 13 pound of meat to make one hamburger. How many hamburgers can Kim make with the meat she has?
Answer:
8
Step-by-step explanation:
.13 times 8 = 1.04
Question 2 (12 marks) A home-printer manufacturer would like to conduct a survey to study their customers' opinion about the photo printer. A new model of photo printer was launched 3 months ago, and 1000 customers have filled in the online warranty cards. Based on the list of these 1000 customers, 20 customers have been selected randomly for the survey. (a) The sample was selected by systematic sampling method. Unique identity numbers were assigned to the customers from0001−1000. Suppose it is known that customer with identity number 0131 was included in the sample. Write down the identity numbers of the next three selected customers after 0131. Below is the summary statistics of the sample: (b) Find the interquartile range and range of the data. (c) Comment on the skewness of the data. Explain your answer with detailed comparison. (d) Another sample of 10 customers have been collected. The sample mean of this sample is 70 and the minimum and maximum data are 50 and 110 respectively. Combine the two samples, find the mean and range for the combined sample with 30 data.
The identity numbers of next three selected customers are 0181, 0231, and 0281. The interquartile range and range is 18 and 30. The data is negatively skewed and the mean and range of combined sample is 41.8 and 60 respectively.
(a) Since the sample was selected using systematic sampling, we can determine the sampling interval by dividing the population size by the sample size:
Sampling interval = Population size / Sample size = 1000 / 20 = 50
Since customer 0131 was included in the sample, the next three selected customers are:
0131 + 50 = 0181
0181 + 50 = 0231
0231 + 50 = 0281
(b) To find the interquartile range, we first need to find the median. Since the sample size is even, we take the average of the middle two values:
Median = (75 + 80) / 2 = 77.5
The first quartile (Q₁) is the median of the lower half of the data, and the third quartile (Q₃) is the median of the upper half of the data. We can use the ordered data to find these values:
Ordered data: 60, 62, 63, 64, 65, 70, 75, 80, 85, 90
Lower half: 60, 62, 63, 64, 65, 70
Upper half: 75, 80, 85, 90
Q₁ = median of lower half = (64 + 65) / 2 = 64.5
Q₃ = median of upper half = (80 + 85) / 2 = 82.5
Therefore, the interquartile range is:
IQR = Q₃ - Q₁ = 82.5 - 64.5 = 18
To find the range, we subtract the minimum value from the maximum value:
Range = 90 - 60 = 30
(c) To comment on the skewness of the data, we can compare the mean, median, and mode. If the mean is equal to the median and mode, then the data is symmetrical. If the mean is greater than the median, then the data is positively skewed. If the mean is less than the median, then the data is negatively skewed.
Mean = (60 + 62 + 63 + 64 + 65 + 70 + 75 + 80 + 85 + 90) / 10 = 72.4
Median = 77.5
Mode = there is no mode
Since the mean is less than the median, the data is negatively skewed.
(d) To find the mean of the combined sample, we can use the formula:
Mean = (sum of all data) / (number of data)
The sum of the data in the original sample is:
60 + 62 + 63 + 64 + 65 + 70 + 75 + 80 + 85 + 90 = 694
The sum of the data in the new sample is:
50 + 60 + 70 + 80 + 90 + 100 + 110 = 560
The sum of all the data is:
694 + 560 = 1254
The number of data is 20 + 10 = 30
Therefore, the mean of the combined sample is:
Mean = 1254 / 30 = 41.8
To find the range of the combined sample, we subtract the minimum value from the maximum value:
Range = 110 - 50 = 60
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The light from the Cape Florida Lighthouse in Key Biscayne is visible for a distance of 15 mi. If the beam of light sweeps in an arc of 270°, what is the area covered by the beam?
The area included by means of the beam of the Cape Florida Lighthouse light is about 177 square miles whilst rounded to the nearest square mile.
To find the area covered by means of the beam of the Cape Florida Lighthouse light, we need to first find the radius of the circle that the beam sweeps over. We recognise that the most distance the mild can be visible is 15 miles, so the radius of the circle is also 15 miles.
Next, we want to discover the valuable attitude of the circle that the beam sweeps over. We know that the beam sweeps in an arc of 270°, which is three-quarters of a complete circle. therefore, the critical attitude of the circle that the beam sweeps over is also 270°.
Now, we are able to use the formula for the area of a sector of a circle to discover the area covered through the beam:
area of sector = (central angle/360°) x π x radius^2
Substituting the given values, we get:
area of sector = (270°/360°) x π x 15^2area of sector = (three/4) x π x 225area of sector = 176.71 square milesThus, the area included by means of the beam of the Cape Florida Lighthouse light is about 177 square miles whilst rounded to the nearest square mile.
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1000x100/2+8-4=____________
Answer:
[tex]16666\frac{2}{3}[/tex]
Step-by-step explanation:
Solving using PEMDAS
[tex]\frac{1000\times 100}{2+8-4}[/tex]
Since this is a fraction, we can work on the top and the bottom. Lets do the top first. Multiply.
[tex]\frac{100000}{2+8-4}[/tex]
Now we can add two, then subtract.
[tex]\frac{100000}{6}[/tex]
Since this yields an irrational number if we divide, we can simplify this fraction.
[tex]16666\frac{2}{3}[/tex]
Two cylinders, A and B, are created. Cylinder B has the same height as Cylinder A. Cylinder B is half the diameter of Cylinder A. Create an expression that presents the volume of cylinder B in terms of the volume of cylinder A,V
Natalie budgets $146 for yoga training. She buys a yoga mat for $10 and spends $9 per day on yoga classes. Which inequality represents the number of days, d, that Natalie can take classes and stay within her budget?
Need some assistance in Math
The cοrrect answer is "Yes, because angle A will still have the same degree measurement in the same pοsitiοn."
What is translatiοn?In mathematics, translatiοn is a geοmetric transfοrmatiοn that invοlves mοving an οbject in a straight line withοut changing its size, shape, οr οrientatiοn. This mοvement can be in any directiοn and at any distance.
The cοrrect answer is "Yes, because angle A will still have the same degree measurement in the same pοsitiοn." This is because an angle is defined by its degree measurement and the twο rays that fοrm it. When an angle is translated (mοved) in sοme way, its degree measurement and the pοsitiοn οf its rays dο nοt change, sο it remains an angle.
Hοwever, if the angle is rοtated οr scaled, its degree measurement and/οr the pοsitiοn οf its rays will change, and it may nο lοnger be an angle in its οriginal fοrm. Translatiοn οnly changes the lοcatiοn οf an οbject, nοt its fοrm οr shape, sο the image οf angle A will still be an angle with the same degree measurement and pοsitiοn οf rays as the οriginal angle A.
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Frank needs to find the area enclosed by the figure. The figure is made by attaching semicircles to each side of a 56-m-by-56-m square. Frank says the area is 1,787. 52m squared. Find the area enclosed by the figure. Use 3. 14 for pi. What error might have made?
The figure's overall area is 8,065.76 square metres (3,136 + 4,929.76 square metres).
To find the area enclosed by the figure, we need to calculate the area of the square and the four semicircles and then add them together. The area of the square is 56 × 56 = 3,136 square meters.
The diameter of each semicircle is equal to the side of the square, which is 56 meters. Therefore, the radius of each semicircle is 28 meters. The area of one semicircle is (1/2) × pi × 28² = 1,232.44 square meters. The area of all four semicircles is 4 × 1,232.44 = 4,929.76 square meters.
Thus, the total area of the figure is 3,136 + 4,929.76 = 8,065.76 square meters.
The error that Frank made is likely in the calculation of the area of the semicircles. He may have used the formula for the area of a circle instead of a semicircle or made a mistake in the calculation. It is also possible that he rounded the area to two decimal places, leading to a small error in the final answer.
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Find the radius of a hemisphere with a volume of 2,712. 3 in3
[tex]\textit{volume of a hemisphere}\\\\ V=\cfrac{2\pi r^3}{3}~~ \begin{cases} r=radius\\[-0.5em] \hrulefill\\ V=2712.3 \end{cases}\implies 2712.3=\cfrac{2\pi r^3}{3}\implies (3)(2712.3)=2\pi r^3 \\\\\\ \cfrac{(3)(2712.3)}{2\pi }=r^3\implies \sqrt[3]{\cfrac{(3)(2712.3)}{2\pi }}=r\implies 10.90\approx r[/tex]
four times the sum of two consecutive even integers is 40. what is the greater of the two even integers?
The greater of the two even integers is 6. The solution has been obtained by using arithmetic operations.
What are arithmetic operations?
The four fundamental operations, often referred to as "arithmetic operations",are said to be able to describe all real numbers. The four mathematical operations following division, multiplication, addition, and subtraction are quotient, product, sum, and difference.
Let the consecutive integers be 'x' and 'x+2'.
We are given that four times the sum of two consecutive even integers is 40.
So,
4 (x + x +2) = 40
On solving this, we get
⇒4 (2x +2) = 40
⇒2x + 2 = 10
⇒2x = 8
⇒x = 4
The next integer will be 6.
Hence, the greater of the two even integers is 6.
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again ignore the erased stuff
The image contains the answer to the questions.
Please help me I want to finish this so I can get the full grade
The population density of the town is 13,000 people per square mile.
How to calculate population density in an area?To calculate the population density in an area, you need two pieces of information: the total population of the area and the total land area of the area. Population density calculation refers to the process of determining the number of individuals living in a particular area, expressed as a ratio or proportion of the size of that area.
[tex]Population Density =\frac{Total Population }{Total Land Area}[/tex]
According to the question the total land area of the town can be calculated as follows:
Total Land Area = 20 blocks x ([tex]\frac{1}{20}[/tex] mile) x ([tex]\frac{1}{2}[/tex] mile) = 0.5 miles²
We are also given that there are 6,500 people in the town. Therefore, the population density can be calculated as follows:
[tex]Population Density =\frac{6,500}{0.5}[/tex] = 13,000 people per square miles.
Therefore, the population density of the town is 13,000 people per square mile.
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