what would I put to show my work?
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Answer:
x = 23
Step-by-step explanation:
These are supplementary angles so the sum of those angles add up to 180:
3x + 16 + 5x - 20 = 180
8x - 4 = 180
8x = 180 + 4
8x = 184
x = 184/8
x = 23