Question

What is the measure of m_A?

Answer 1

m∠A=52°

Explanation:

Because of the exterior angle theorem, m∠A+m∠B=105° (The exterior angle)

We then end up with an equation like this...

m∠A+m∠B=105°

Then, you do the substitution...

x+53°=105°

Subtract 53 from both sides...

x=105°-53°

x=52°