Given:


To find:
The value of x and measure of ∠A.
Solution:
Let C be angle the vertically opposite to ∠A.
The reference image for answer is attached below.
By vertical angle theorem:
m∠A = m∠C
m∠C = 10x + 24°
By the corresponding angle theorem:
m∠C = m∠B

Subtract 24° on both sides.

Subtract 6x from both sides.

Divide by 4 on both sides.

The value of x is 12°.



The measure of ∠A is 144°.