You can put this solution on YOUR website! tan(theta - 10) = cot(2 theta + 17)
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Note: tan and cot are complementary functions
cot(x) = tan(90-x)
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Your problem:
cot(90-(t-10)) = cot(2t + 17)
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90-t+10 = 2t+17
3t = 100-17
3t = 83/3
t = 27 1/3
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Cheers,
Stan H.