100 points pic attached will mark brainliest random answers will be reported

Answer: B

Step-by-step explanation:

there are 36 quarters.

Let the number of nickels be x

Let the number of quarters be y

Value Value

Type Number of of

of of EACH ALL

coin coins coin coins

-------------------------------------------

nickels x $0.05 $0.05x

quarters y $0.25 $0.25y

-------------------------------------------

TOTALS 52 ----- $3.60

The first equation comes from the second column.

x + y = 11

The second equation comes from the last column.

0.05x + 0.25y = 3.60

Get rid of decimals by multiplying every term by 100:

5x + 25y = 360

So we have the system of equations:

x+y=52

5x+25y=360

We solve by substitution. Solve the first equation for y:

x + y = 52

y = 52 - x

Substitute (52 - x) for y in 5x + 25y = 360

5x + 25(52 - x) = 360

5x + 1300 - 25x = 360

-20x + 1300 = 360

-20x = -940

x = = 5 the number of nickels.

Substitute in y = 52 - x

y = 52 - (5

y = 47 quarters.

The number of quarters is 52-x or 52-5 or 47 quarters.

9514 1404 393

Answer:

  (x, y) = (1, 1)

Step-by-step explanation:

About Algebra

All of Algebra is based on a few simple rules:

When we solve equations by substitution, we make use of these facts.

__

About Substitution

Generally, substitution in equation solving is done for the purpose of eliminating a variable from the equation. That usually means you want to write an expression for one variable in terms of other variables.

Finding the Expression to Substitute

In this set of equations, the variables are x and y. We can substitute for y an expression involving x, or we can substitute for x an expression involving y. These equations are written in such a way that either method works as well as the other.

Let's choose to substitute for y. This means we need an equation of the form ...

  y = <some expression involving x>

The first equation makes it easy to get that. If we add y (to both sides, see rule 3 above), we get ...

  5x -y +y = 4 +y

  5x = 4 + y . . . . . . . . . simplified

Subtracting 4 (from both sides) gets us the form we want.

  5x -4 = 4 -4 + y

  5x -4 = y . . . . . . by rule 4 above, we can use (5x-4) anyplace you see y

Using the Expression to Substitute

Now, we have an expression for y that we can use in the second equation. There, y is multiplied by 4, so we need to be sure to multiply the whole expression by 4:

  -x + 4(5x -4) = 3 . . . . . . substituted for y in the second equation

  -x +20x -16 = 3 . . . . . use the distributive property to eliminate parentheses

  19x -16 = 3 . . . .  . . collect terms

This has a constant (-16) where we don't want it, so we can add 16 (to both sides) to get rid of it.

  19x -16 +16 = 3 +16

  19x = 19 . . . . simplify

Now, we can divide by 19 (to both sides) to get x by itself.

  (19x)/19 = 19/19

  x = 1 . . . . almost done; we still need to find y

Finishing Up

Using the equation for y that we used for substitution, we can find y from our value of x.

  y = 5x -4 = 5×1 -4 = 5-4

  y = 1

So, the solution is x = 1, y = 1, or (x, y) = (1, 1).

_____

Additional comment

In this set of equations, both variables (x and y) appear with coefficients of 1 (actually, -1). This makes it easy to solve for an expression that can be substituted for the variable. In systems of equations that you want to solve by substitution, it usually works well to start by looking for a variable with a coefficient of 1 (or -1). Use that to write the substitution expression as we did here.

__

Alternate Solution

If you use a variable with a coefficient other than 1 to write the substitution expression, you end up with fractions. That's OK if you're comfortable with arithmetic using fractions. It generally requires more care.

For example, we could solve the first equation for x:

  x = (4 +y)/5

Substituting that into the second equation gives ...

  -(4 +y)/5 +4y = 3

  -4/5 -y/5 +4y = 3

  (3 4/5)y = 3 4/5 . . . . . add 4/5 (to both sides), collect terms

Now, you get to divide by 3 4/5 to get ...

  y = (3 4/5)/(3 4/5) = 1

Fortunately, in this case, we can see the numerator and denominator are identical, so the division result is 1. If it weren't you'd be faced with dividing mixed numbers--not always a student's first choice of fun math operations.

  x = (4 +1)/5 = 1 . . . . finishing up

Answer:

3

Step-by-step explanation:

3 * 2 1/4 = 6 3/4

Answer:

dial it up

2:16

simplify

1:8

now multiply 8 by the number of gigs

2:16

3:24

and so on.....

ring ring

1:9

again multiply the cost by the number of gigs

2:18

3:27

and so on....

Answer:

70 i am 100 percent sure

Step-by-step explanation:

1:10

7     70

Answer:

For the first problem the answer is x=4

The second Problem the answer is no solutions

Step-by-step explanation:

7x−(3x+5)−8=1/2 (8x+20)−7x+5

7x+−3x+−5+−8=1/2(8x) +(1/2) (20)+−7x+5(Distribute)

7x+−3x+−5+−8=4x+10+−7x+5

(7x+−3x)+(−5+−8)=(4x+−7x)+(10+5)(Combine Like Terms)

4x+−13=−3x+15

4x−13=−3x+15

Step 2: Add 3x to both sides.

4x−13+3x=−3x+15+3x

7x−13=15

Add 13 to both sides.

7x−13+13=15+13

7x=28 Divide both sides by 7.

x=4

5(3x+4) -2x = 7x -3(-2x+11)​

Simplify both sides of the equation.

5(3x+4)−2x=7x−3(−2x+11)

(5)(3x)+(5)(4)+−2x=7x+(−3)(−2x)+(−3)(11)(Distribute)

15x+20+−2x=7x+6x+−33

(15x+−2x)+(20)=(7x+6x)+(−33)(Combine Like Terms)

13x+20=13x+−33

13x+20=13x−33

Subtract 13x from both sides.

13x+20−13x=13x−33−13x

20=−33

Step 3: Subtract 20 from both sides.

20−20=−33−20

0=−53

There are no solutions.

Answer:

Step-by-step explanation:

7x-(3x+5)-8 = (1/2)*(8x+20) -7x +5

1. Distributive Property

7x - 3x - 5 - 8 = 4x + 20 - 7x + 5

2. Combine like terms

4x -13 = -3x + 25

3. Add 13 on both sides

4x -13 + 13 = -3x + 25 + 13

4x = -3x + 38

4. Add 3x on both sides

4x + 3x = -3x + 3x + 38

7x = 38

5. Divide by 7 on both sides

7x / 7= 38 / 7

x = 5.428571428571429

or

x = 5.4

__________________________________________________________

5(3x+4) -2x = 7x -3(-2x+11)​

1. Distributive Property

15x + 20 - 2x = 7x + 6x - 33

2. Combine like terms

13x + 20 = 13x - 33

3. Subtract 20 on both sides

13x + 20 - 20 = 13x - 33 - 20

13x = 13x - 53

4. Subtract 13x on both sides

13x - 13x = 13x - 13x - 53

0 = -53 ( there is no answer for x)

Hope this helped!!!!

Answer: A.  the price for a shirt that originally cost s after a 21% discount

Step-by-step explanation:

Answer:

f (4) = 21

Step-by-step explanation:

the given equation is f (x) = 4x + 5

putting the value of x = 4

we get, f (4) = (4×4) + 5

f (4) = 16 + 5

f (4) = 21

i hope u got it

Answer:

x = 8

Step-by-step explanation:

Let the number = x

x/6 - 1/3 = x/8

-1/3 = x/8 - x/6

-1/3 = (6x-8x)/48

-1/3 = -2/48x

Divide both sides by -2/48

x = -1/3 ÷ -2/48

= -1/3 × -48/2

= 48/6

= 8

x = 8

The number = 8

Answer:

19

Step-by-step explanation:

[tex]\displaystyle K_c \approx 0.0424[/tex]

Math

Pre-Algebra

Order of Operations: BPEMDAS

Chemistry

Equilibrium

Step 1: Define

[RxN]   2NO₂ ⇆ N₂O₄

[Equilibrium Rate Law]   [tex]\displaystyle K_c = \frac{[N_2O_4]}{[NO_2]^2}[/tex]

NO₂ = 11.95 M

N₂O₄ = 6.05 M

Step 2: Find K

This value of K tells us that the reactants are favored in the equilibrium reaction (K < 0.1).

Answer:

can someone give us the answer if its independent or dependent

Step-by-step explanation:

Answer:

[tex]8 \sqrt{72} = 8 \sqrt{3 \times 3 \times 2 \times 2 \times 2} \\ = 8 \times 3 \times 2 \times \sqrt{2} = 48 \sqrt{2} [/tex]

Answer:

17:14 or 17 to 14

Step-by-step explanation:

since you know there are 14 girls, subtract 14 from 31 and then you'll get 17. since its asking for a ratio of boys to girls not girls to boys, you put boys first, then girls. so your answer will be 17:14

Answer:

where are the squares?

Step-by-step explanation:

Step-by-step explanation:

400,200,100,50,25,12.5, ...... 0.78125

Solution

here, length= 5cm

breath= ?

Perimeter= 86 cm

By the question,

Perimeter (P) = l×b = 86 cm

or, 5cm × b= 86 cm

or, b = 86÷ 5

or, b= 17.2 cm

Step-by-step explanation:

multiply 5x+2y=19 by 3 youll get 15x+6y=57

eliminate y

7x-6y=9

15x+6y=57 +

22x=66

x=3

substitute x to 5x+2y=19

15+2y=19

2y=4

y=2

Answer:

The submarine gains 120 feet of elevation per minute.

Step-by-step explanation:

Answer:d) g(x)=x^1/3-1.5

Step-by-step explanation:

Answer:

slope= ( 5,1 ) Y-intercept= ( 0,-7 )

Step-by-step explanation:

Answer:

the answer is option : D

Step-by-step explanation:

multiply 9 with the given hrs to find the correct one

Answer:

hypotenuse = 4.24

Step-by-step explanation:

sin θ = opposite / hypotenuse

sin 45 = 3[tex]\sqrt{2}[/tex]/ hypotenuse

0.707 = 3[tex]\sqrt{2}[/tex]/ hypotenuse

hypotenuse = 4.24

Answer:

Write a situation in which positive and negative numbers are used to describe values that have opposite meaning. What does 0 represent in this situation you created?

Step-by-step explanation:

Answer:

p=23

Step-by-step explanation:

Answer:

P=23

Step-by-step explanation:

38-15=23

p=23

Hope this helps

Have a great day!

Answer:

i think its c 6-6 so good luck