HELP MEEEEEEEEEEEEEEEEE!
X +(X+1)+...+2020+2021=2021
If x is an integer, and
x + (x + 1) + … + 2020 + 2021 = 2021
then of course
x + (x + 1) + … + 2020 = 0
and we can write the left side as a sum,
[tex]\displaystyle \sum_{k=0}^n (x+k) = 0[/tex]
with n such that x + n = 2020. (Notice that there are n + 1 terms in the sum.) Then x = 2020 - n, so that
[tex]\displaystyle \sum_{k=0}^n (2020 - n + k) = (2020 - n) \sum_{k=0}^n 1 + \sum_{k=0}^n k= 0[/tex]
Recall that
[tex]\displaystyle \sum_{k=1}^n 1 = 1 + 1 + 1 + \cdots + 1 = n[/tex]
[tex]\displaystyle \sum_{k=1}^n 1 = 1 + 2 + 3 + \cdots + n = \frac{n(n+1)}2[/tex]
Then
[tex]\displaystyle (2020 - n) (n + 1) + \frac{n(n+1)}2= 0[/tex]
Solve for n :
(2020 - n) (n + 1) + n (n + 1) / 2 = 0
4040 + 4039 n - n² = 0
(n - 4040) (n + 1) = 0
⇒ n = 4040 or n = -1
But we are taking the sum of a positive number of terms, so n = 4040.
Then since x + n = 2020, it follows that x = 2020 - 4040 = -2020.
Answer as soon as possible I’ll give 5 stars!!!
Answer:
B
Step-by-step explanation:
2 times x is 2x
2*8=16
its B
Hey there!
2(x + 8)
DISTRIBUTE 2 WITHIN THE PARENTHESES
= 2(x) + 2(8)
= 2x + 16
Therefore, your answer should be: 2x + 16
Good luck on your assignment and enjoy your day!
~Amphitrite1040:)
Find the value of 5x + 6 when x = -2
Answer:
- 4
Step-by-step explanation:
Substitute x = - 2 into the expression
5x + 6 = 5(- 2) + 6 = - 10 + 6 = - 4
Writing a ratlo as a percentage
Manuel has ridden 8 miles of a bike course. The course is 20 miles long. What percentage of the course has Manuel ridden so far?
0
se
%
X 5
?
Using substitution, evaluate the expression b-a, if a = -14 and b = -7.
O 21
O -21
-7
7.
Please help
In class A, 17 students in a class of 25 passed an exam. In class B, 13 out of 20 passed. In class C, 7 out of 10 passed. Which class is the best class?
Answer:
class C
Step-by-step explanation:
a=(17/25)=0.68
b=(13/20)=0.65
c=(7/10)=0.7
14. A triangle has vertices at A(4,2), B(-4,-2), and
C(2, 4). If the triangle is dilated with respect to the
origin using a scale factor of 172, what will the
coordinates for the new vertices be?
A A' (2.1). B' (-2,-1), and C (1.-2)
B. A (8.4), B (-8,-4). and C (4. - 8)
C. A' (1,2), B (-1,-2), and C (-2. - 1)
D. A (-2,-1), B' (-2,-1), and C° (-1,2)
Answer:
A
Step-by-step explanation:
Each coordinate of the triangle will have to dilate by 1/2 in order for the triangle to be fully dilated. Let's check each option to see which one has the correctly dilated points.
First, we'll look at A. A(4, 2) goes to A'(2, 1)... which is looking good so far! Half of 4 is 2, and half of 2 is 1, so the right dilation was applied. Next, let's check out B. B(-4, -2) goes to B'(-2, -1), which is still looking okay. Half of -4 is -2, and half of -2 is -1. Finally, we'll check the point C. If this one is correctly dilated, option A is the right option. C(2, -4) goes to C'(1, -2), and we can now be sure that option A is correct. Half of 2 is 1, and half of -4 is -2.
So, option A is the one to select. Hopefully that's helpful! :)
Determine whether each graph shows a positive correlation, a negative
correlation, or no correlation. If there is a positive or negative correlation,
describe its meaning in the situation.
Answer:
\huge\purple{ 〇 }〇 \huge\blue{ △ }△ \huge\orange{ ☆ }☆ \huge\pink{ ☂ }☂ \huge\purple{ 〇 }〇 \huge\blue{ △ }△ \huge\orange{ ☆ }☆ \huge\pink{ ☂ }☂ \huge\purple{ 〇 }〇 \huge\blue{ △ }△ \huge\orange{ ☆ }☆ \huge\pink{ ☂ }☂ \huge\purple{ 〇 }〇 \huge\blue{ △ }△ \huge\orange{ ☆ }☆ \huge\pink{ ☂ }☂ \huge\purple{ 〇 }〇 \huge\blue{ △ }△ \huge\orange{ ☆ }☆ \huge\pink{ ☂ }☂ \huge\purple{ 〇 }〇 \huge\blue{ △ }△ \huge\orange{ ☆ }☆ \huge\pink{ ☂ }☂ \huge\purple{ 〇 }〇 \huge\blue{ △ }△ \huge\orange{ ☆ }☆ \huge\pink{ ☂ }☂ \huge\purple{ 〇 }〇 \huge\blue{ △ }△ \huge\orange{ ☆ }☆ \huge\pink{ ☂ }☂
Answer:
Negative correlation
Step-by-step explanation:
As TV hours increase, exercise hours decrease.
help please its overdue
Answer:
B) 4cm
Step-by-step explanation:
Hope this helps! Pls give brainliest!
20. Write an expression: Alexis has $10 less than twice the amount that David has. If David has
x dollars, write an expression to represent the amount that Alexis has.
Answer:
2x - 10
Step-by-step explanation:
'x' = amount David has
Alexis = 2x - 10
If the cubic function P(x) includes the points (−4, 0), (0, 0), and (2, 0), which of the following represents this function?
Answer:
See below
Step-by-step explanation:
(-4,0) is the solution to x+4=0
(0,0) is the solution to x=0
(2,0) is the solution to x-2=0
Therefore, (x+4)(x-2)(x) = (x²-2x+4x-8)(x) = (x²+2x-8)(x) = x³+2x²-8x is the function that has the given zeroes
Help!! Simplify the expression?
Answer:
Here is my answer I have solved hope this helps
If a number has 8 as a factor, then both 2 and 4 are factors
The weights of a certain brand of candies are normally distributed with a mean weight of 0.8593 g and a standard deviation of 0.0511 g. A sample of these candies came from a package containing 464 candies, and the package label stated that the net weight is 396.1 g. (If every package has 464 candies, the mean weight of the candies must exceed 396.1 464=0.8537 g for the net contents to weigh at least 396.1 g.)
Answer:
The package label stated that the net weight is 381.8g If every package has ... brand of candies have a mean weight of 0.8616g and a standard deviation of ...
Chi is planning to put a path of paving stones through her flower garden. The flower garden is a square with sides of 15 feet. How many feet long will the path be? Round your answer to one decimal place.
[(15×2)+(15×2)]=60=6.0
What’s 12.71 divided 6.2?
Answer:
2.05
Step-by-step explanation:
12.71/6.2=2.05
The value of the expression 12.71 ÷ 6.2 using the division property will be 2.05.
What is Algebra?Algebra is the study of algebraic expressions, while logic is the manipulation of those concepts.
The acronym PEMDAS stands for Parenthesis, Exponent, Multiplication, Division, Addition, and Subtraction. This rule is used to answer the problem correctly and precisely.
The numbers are given below.
12.71 and 6.2
Then the division of the decimal numbers 12.71 and 6.2 will be given by putting a divide sign between them. Then we have
⇒ 12.71 ÷ 6.2
⇒ 12.71 / 6.2
⇒ 2.05
The worth of the articulation 12.71 ÷ 6.2 utilizing the division property will be 2.05.
More about the Algebra link is given below.
https://brainly.com/question/953809
#SPJ2
if you roll a fair 6-sided die 9 times, what is the probability that at least 2 of the rolls come up as a 3 or a 4?
Using the binomial distribution, it is found that there is a 0.857 = 85.7% probability that at least 2 of the rolls come up as a 3 or a 4.
For each die, there are only two possible outcomes, either a 3 or a 4 is rolled, or it is not. The result of a roll is independent of any other roll, hence, the binomial distribution is used to solve this question.
Binomial probability distribution
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]
The parameters are:
x is the number of successes. n is the number of trials. p is the probability of a success on a single trial.In this problem:
There are 9 rolls, hence [tex]n = 9[/tex].Of the six sides, 2 are 3 or 4, hence [tex]p = \frac{2}{6} = 0.3333[/tex]The desired probability is:
[tex]P(X \geq 2) = 1 - P(X < 2)[/tex]
In which:
[tex]P(X < 2) = P(X = 0) + P(X = 1)[/tex]
Then
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]P(X = 0) = C_{9,0}.(0.3333)^{0}.(0.6667)^{9} = 0.026[/tex]
[tex]P(X = 1) = C_{9,1}.(0.3333)^{1}.(0.6667)^{8} = 0.117[/tex]
Then:
[tex]P(X < 2) = P(X = 0) + P(X = 1) = 0.026 + 0.117 = 0.143[/tex]
[tex]P(X \geq 2) = 1 - P(X < 2) = 1 - 0.143 = 0.857[/tex]
0.857 = 85.7% probability that at least 2 of the rolls come up as a 3 or a 4.
For more on the binomial distribution, you can check https://brainly.com/question/24863377
1) Solve for x (11 - 2*) 7 = 21
ok done. Thank to me :>
You plant 9 rows of different bulbs in a garden. For each row, you use the rule, “onion, onion, garlic, flower.” How many garlic and flower bulbs do you plant altogether? How many bulbs do you use in all?
Answer: Who the actual fudge gardens anymore????? like what are you an old lady? ur name edna? ethel? doreen? geez louise u are old.
Step-by-step explanation:
Howie wants to get a car loan with 4% simple interest rate. If the car costs $25,000, how much would Howie need to pay back at the end of one year, including the interest?
The amount Howie will pay back at the end of one year is $26000.00
The given parameters are:
[tex]P =25000[/tex] -- the principal amount
[tex]R = 4\%[/tex] -- the interest rate
[tex]T=1[/tex] --- the duration
The amount to pay back in this duration is then calculated using:
[tex]A = P(1 + RT)[/tex]
So, we have:
[tex]A = 25000(1 + 4\% \times 1)[/tex]
[tex]A = 25000(1 + 4\% )[/tex]
Express percentage as decimal
[tex]A = 25000(1 + 0.04)[/tex]
[tex]A = 25000(1 .04)\\[/tex]
Multiply
[tex]A = 26000[/tex]
Hence, the amount to pay back is $26000.00
Read more about simple interest at:
https://brainly.com/question/1115815
If 108 is added to a number, it will be 5 times as large as it was originally. Find the number.
Answer:
27
Step-by-step explanation:
let th original number=x
x+108=5x
5x-x=108
4x=108
x=108/4=27
what is solve 10<-2/3(9+12b)
Segments CD, GH, and JK intersect point A.
Answer: HK
Step-by-step explanation:
Find the 53" term of the following arithmetic sequence.
3, 11, 19, 27, ...
Answer:
419
Step-by-step explanation:
a=3
d=11-3=8
[tex]a_{n}=a+(n-1)d\\n=53\\a_{53}=3+(53-1)*8\\=3+52*8\\=3+416\\=419[/tex]
The formula N(x) = x2 -2x + 2016 represents the number N of gang-related homicides across the country x years after 2017. According to this formula, in what year will the number of gang-related homicides be 2051?
Answer:
Graph the parabola using the direction, vertex, focus, and axis of symmetry.
Direction: Opens Up
Vertex:
(
1
,
2015
)
Focus:
(
1
,
8061
4
)
Axis of Symmetry:
x
=
1
Directrix:
y
=
8059
4
x
y
−
1
2019
0
2016
1
2015
2
2016
3
2019
Step-by-step explanation:
The number of gang-related homicides in 2051 will be 3,104.
What is a function?A function is an assertion, concept, or principle that establishes an association between two variables. Functions may be found throughout mathematics and are essential for the development of significant links.
The function is given below.
N(x) = x² -2x + 2016
N represents the number of gang-related homicides across the country x years after 2017.
Then the number of gang-related homicides be 2051 will be given as,
N(2051 - 2017) = (2051 - 2017)² - 2(2051 - 2017) + 2016
N(34) = 34² - 2(34) + 2016
N(34) = 1156 - 68 + 2016
N(34) = 3,104
The quantity of pack-related homicides in 2051 will be 3,104.
More about the function link is given below.
https://brainly.com/question/5245372
#SPJ2
Please help!! markup and markdown word problems.
1. A boat is marked up 20% on the original price. The original price was $50. What is the sale price of the boat before sales tax?
2. Fred buys a video game disk for $4. There was a discount of 20%. What is the sales price?
3. A painting is on sale at 50% off. The sale price is $320. What was the original price?
Answer:
Step-by-step explanation:
1. A boat is marked up 20% on the original price. The original price was $50. What is the sale price of the boat before sales tax?
$50(1+0.20) = $60
2. Fred buys a video game disk for $4. There was a discount of 20%. What is the sales price?
$4(1-0.2) = $3.20
3. A painting is on sale at 50% off. The sale price is $320. What was the original price?
X*(1-0.5) = $320
X = $320/0.5
X = $640
Three more than a positive number is twenty less than it’s square. What is the number ?
Answer:
the +ve no. = 2
Step-by-step explanation:
let the number be x - 3
three more than a positive number = x
acc. to condition
x^{2}x
2
- 20 = x
x^{2} - x - 20 = 0x
2
−x−20=0
x^{2} - 5x + 4x - 20 = 0x
2
−5x+4x−20=0
x(x - 5) +4(x - 5) = 0x(x−5)+4(x−5)=0
(x+4)(x-5) = 0(x+4)(x−5)=0
Case 1
x + 4 = 0x+4=0
x = -4x=−4
the Number cannot be negative because the condition given in question
Case 2
x - 5 = 0x−5=0
x = 5x=5
Hence, the positive number
= x - 3=x−3
= 5 - 3=5−3
= 2=2 hope i help you
In the art club, there are 2 seventh graders for every 3 eighth graders. At
this year's art fair, there were 7 paintings by seventh graders for every 12
paintings by eighth graders. Is the ratio of seventh graders to eighth
graders in the art club equivalent to the ratio of paintings by seventh
graders to paintings by eighth graders? *
Answer:
no
Step-by-step explanation:
2/3 does not equal 7/12.
there would need to be 8 paintings by seventh graders for every 12 by eighth graders in order to have an equivalent ratio.
What is the vertical shift for the absolute value function below f(x) =9 |x+1|+2
Answer:
Slide UP 2
Step-by-step explanation:
In the equation,
f(x) = 9|x+1| + 2
There are three transformations of the parent function f(x)=|x| (this is the simplest form of this function, it's a v-shaped graph)
The 9 in front will vertically stretch the graph and make it look like a "skinny" v-shaped graph.
The +1 in close to the x inside the absolute value bars |x+1| will shift (slide) the graph to the left (it's the opposite of what you might think-- 'plus' shifts the graph left and 'minus' shifts the graph right)
The +2 at the end is the transformation you're looking for. It slides the graph as you would expect UP 2 units. If it was a minus it would shift the graph down instead.
find the mean of 98 100 100 100 100 100
Answer:
the mean of this sequence of numbers is 99
Answer:
it is 99
Step-by-step explanation: