**Answer:**

y = 130

**Step-by-step explanation:**

(4x+8) + (3x-19) + (x+7) = 180

4x + 8 + 3x - 19 + x + 7 = 180

(4x + 3x + x) + (8 -19 + 7) = 180

8x - 4 = 180

8x -4 +4 = 180 +4

8x = 184

8x/8 = 184/8

x = 23

3(23) - 19 = 50

50 + y = 180

180 - 50 = y

y = 130

**Answer:**

1350m

**Step-by-step explanation:**

Let the distance ran by Denise, Farah and Elaine be D, F and E meters respectively.

From the given information,

D= ⅔(E +F) -----(1)

E= ½(D +F) -----(2)

Let's get rid of the fraction so the equations are much easier to work with.

From (1):

3D= 2(E +F) <em>(Multiply both sides by 3)</em>

3D= 2E +2F -----(3) <em>(</em><em>Expand</em><em>)</em>

From (2):

2E= D +F -----(4)

Substitute (4) into (3):

3D= D +F +2F

3D -D= 3F

2D= 3F

Given that Farah ran 360m, F= 360.

2D= 3(360)

2D= 1080

D= 1080 ÷2

D= 540

2E= D +F

2E= 540 +360

2E= 900

E= 900 ÷2

E= 450

Total distance the 3 girls ran

= D +F +E

= 540 +360 +450

= **1350m**

Alternatively, you could start by substituting F= 360 to equations (1) and (2).

C. m∠x=90-40=50°

m∠y=180-55=125°

**Answer:**

48m+12

**Step-by-step explanation:**

6(m+2+7m)=6m+12+42m=48m+12