Answer: x = 22
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Work Shown:
The given angles are a linear pair, so they are supplementary.
(1+5x)+(3+3x) = 180
1+5x+3+3x = 180
(5x+3x)+(1+3) = 180
8x+4 = 180
8x+4-4 = 180-4 .... subtract 4 from both sides
8x = 176
8x/8 = 176/8 ..... divide both sides by 8
x = 22
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Extra info:
1+5x = 1+5*22 = 1+110 = 111
3+3x = 3+3*22 = 3+66 = 69
111+69 = 180, which helps confirm the answer.