Question

∠A and ​ ∠B ​ are vertical angles with m∠A=x and m∠B=3x−60 . What is m∠A ?

Answer 1

m∠A=30°

Explanation:

we know that

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

Vertical angles always are congruent

In this problem

m∠A=m∠B ----> by vertical angles

we have

m∠A=x

m∠B=3x-60

substitute

`3x-60=x`

Solve for x

`3x-x=60`

`2x=60`

`x=30`

therefore

m∠A=30°