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
[tex]x=4x-30[/tex]
Solve for x
[tex]4x-x=30\\3x=30\\x=10[/tex]
Find the measure of angle A
m∠A=x
substitute the value of x
m∠A=10°
