SOLUTION: if cotx + cosecx = 1.5, then prove that cosx = 5/13

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Question 734052: if cotx + cosecx = 1.5, then prove that cosx = 5/13
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
if cotx + cosecx = 1.5, then prove that cosx = 5/13
let O=opposite side
let A=adjacent side
let H=hypotenuse
..
cosx=5/13=A/H
A=5, H=13
O=sqrt%28H%5E2-A%5E2%29=sqrt%2813%5E2-5%5E2%29=sqrt%28169-25%29=sqrt%28144%29=12
cotx=A%2FO=5%2F12
cscx=H%2FO=13%2F12
cotx%2Bcscx=18%2F12=1.5
This proves that if cotx+cscx=1.5, cosx = 5/13, because both equations come from the same 5-12-13 right triangle