The answer is given above
You can just simplify to make an equivalent equation:
(2)(3x + 8) = 5 ⇒ 6x + 16 = 5
Answer:

Hope it helped,
BioTeacher101
<em>(If you have any questions feel free to ask them in the comments)</em>
Ratios equivalent to 5:1 are
10:2
15:3
Supplementary angle = 180
180 - 51 = x
x = 129
C) 129 degrees is your answer
hope this helps