Question

Please explain how this digraph works.

Answer 1

Angles XQL and MQR are congruent because they are vertical angles. So

209 - 13 b = 146 - 4 b

Solve for b :

209 - 13 b = 146 - 4 b

209 - 146 = 13 b - 4 b

63 = 9 b

b = 63/9 = 7

Then the measure of angle XQL is

(209 - 13*7)º = 118º