Question

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

Answer 1

As they are vertical angles, their magnitude would be equal.
x = 3x - 60
3x - x = 60
2x = 60
 x= 30

In short, Your Answer would be 30

Hope this helps!