Question

Consider the figure:

If $\angle$A = ${50}^{\circ }$​, $\angle$B = ${70}^{\circ }$​, and x = 2y, then find the value of y (in degrees).

___

Answer 1

Given, x + y = $\angle A+\angle B$ (exterior angle property)

= ${50}^{\circ }$​ + ${70}^{\circ }$​
= ${120}^{\circ }$​
and, x = 2y, we have
3y = ${120}^{\circ }$​
y = ${40}^{\circ }$​