Answer:
x = 21
Explanation:
The angle adjacent to 3x + 2 corresponds to 5x + 10 and are congruent.
The 2 adjacent angles then lie on a straight line and sum to 180° , then
5x + 10 + 3x + 2 = 180
8x + 12 = 180 ( subtract 12 from both sides )
8x = 168 ( divide both sides by 8 )
x = 21