Question

Find the value of x. Then find the measure of each labeled angle. x = 37.5; the labeled angles are 77.5º and 102.5º. x = 37.5; the labeled angles are 37.5º and 142.5º. x = 15; both labeled angles are 55º. x = 25; both labeled angles are 65º.

Answer 1

x = 25; both labeled angles are 65º

Explanation:

To find the value of x, recall that the angles formed by two parallel lines on the same line are equal if they correspond to each other.

In the figure given above, we have two parallel line given. The angle formed by each parallel line is corresponding to the other. Therefore, both angles formed are equal.

Thus,

(3x - 10)° = (x + 40)°

Solve for x

3x - 10 = x + 40

Subtract x from both sides

3x - 10 - x = x + 40 - x

3x - x - 10 = x - x + 40

2x - 10 = 40

Add 10 to both sides

2x - 10 + 10 = 40 + 10

2x = 50

Divide both sides by 2

2x/2 = 50/2

x = 25

*Plug in the value of x to find the measure of each labelled angles:

(3x - 10)° = 3(25) - 10 = 75 - 10 = 65°

(x + 40)° = 25 + 40 = 65°