Question

∠A

Answer 1

Answer:

m∠A=10°

Step-by-step explanation:

we know that

Vertical angles are the angles opposite each other when two lines cross. The angles are congruent.

so

In this problem we have

m∠A=m∠B

substitute the given values

$x=4x-30$

Solve for x

$4x-x=30\\3x=30\\x=10$

Find the measure of angle A

m∠A=x

substitute the value of x

m∠A=10°