31) x = 25 degrees
Equation: (2x+15) + x + 90 = 180 degrees
--> 3x+105 = 180
-------> 3x = 75
-------------> x = 25 degrees
32) x = 17 degrees
Equation: (x+52) + (3x+21) + 39 = 180 degrees
--> 4x+112 = 180
-------> 4x = 68
-------------> x = 17 degrees