When a and b are parallel.
The sum of supplementary angles is180º
m ∠ b + m ∠ a = 180º
(4x-5)+ (13x -2)= 180º
17 x -7 = 180ª
17 x = 180 +7
x= 187/ 17
x = 11
5.2m questions
6.8m answers