SOLUTION: Find sinx and cosx if tanx=3/4 and sin is greater than 0. Use the Pythagorean identities rather than reference triangles.

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Question 903351: Find sinx and cosx if tanx=3/4 and sin is greater than 0. Use the Pythagorean identities rather than reference triangles.
Found 2 solutions by mananth, lwsshak3:
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
tan x = 3/4
tanx = rise/run = 3/4
rise=3k
run=4k


hypotenuse r = sqrt(3k)^2+(4k)^2)
r= sqrt((3k)^2+(4k)^2)
r=sqrt(9k^2+16k^2)
=sqrt(25k^2)
=5k
sin x = 3k/5k = 3/5
cos x = 4k/5k = 4/5

Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
Find sinx and cosx if tanx=3/4 and sin is greater than 0. Use the Pythagorean identities rather than reference triangles.
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sec^2x=tan^2x+1=(3/4)^2+1=(9/16)+1=25/16
secx=5/4
cosx=4/5
sinx=3/5