use angle addition postulate:
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1) angle (2x+10) and (x+5) are supplementary, meaning they add up to 180 degrees so
(2x+10)+(x+5)=180
3x+15=180
x=55
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2) angle (x-30) and x are complementary, meaning they add up to 90 degrees
(x-30)+x=90
2x-30=90
x=60