SOLUTION: If tan(x)=5/4 and sin is less than 0, find cos(x). Thanks

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Question 974438: If tan(x)=5/4 and sin is less than 0, find cos(x). Thanks
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
If tan(x)=5/4 and sin is less than 0, find cos(x).
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Reference angle x is in quadrant III, where sin<0, cos<0
Hypotenuse of reference right triangle=√(5^2+4^2)=√(25+16)=√41
cos(x)=-4/√41=-(4√41)/41