If they are complementary angles
5x - 8 + 2x - 0 = 90
5x + 2x = 90 + 8
7x = 98
x = 98/7
x = 14
a) angle 1 = 5(14) - 8
= 70 - 8
= 62°
b) angle 2 = 2(14)
= 28°
Then angle 1 + angle 2 = 90°
62 + 28 = 90
90°
2) Supplementary angles
angle 1 = 6x - 19 angle 2 = 15x - 11
6x - 19 + 15x -11 = 180
6x + 15x = 180 + 19 + 11
21x = 210
x = 210/21
x = 10
angle 1 = 6(10) - 19 angle 2 = 15(10) -11
= 60 - 19 = 150 - 11
= 41° = 139°
41 + 139 = 180
180 = 180