Hi! I am not quite sure about the answer, but maybe try an equation I learned: y=kx and y/x = x? Maybe try and subtract the fractions or cross equalize? I am happy to give ideas!
Its B
All you have to do is subtract 10-12 = -2 and 2(5-6) = -2 how? Subtract 5-6 that will equal to -1 now -1 x 2 = -2
- linear pairs are supplementary, meaning they add up to 180°
5x + 9 + 3x + 11 = 180
8x + 20 = 180
8x = 160
x = 20
- now plug in.
angle 1: 5(20) + 9 = 100 + 9 = 109°
angle 2: 3(20) + 11 = 60 + 11 = 71°