The two angles here are supplementary angles, meaning that there sum is 180
Step 1: Set 146 plus -39 + x equal to 180
146 + (-39) + x = 180
146 - 39 + x = 180
Step 2: On the left side of the equation combine like terms
146 and -39 need to be combined, which will give you...
107
New equation:
107 + x = 180
Step 3: Isolate x by subtracting 107 to both sides
(107 -107) + x = 180 - 107
x = 73
Hope this helped!
