SOLUTION: I can't seem to figure this question out....thankful for any help 9x^4=25x^2-16

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Question 12902: I can't seem to figure this question out....thankful for any help
9x^4=25x^2-16
Answer by kusha(21) About Me  (Show Source):
You can put this solution on YOUR website!
let x.x = y & this shall become a quad eqn in y viz
9y.y = 25y - 16
9y.y -16y -9y+16 = 0
(9y-16)(y-1) = 0
y= 16/9 or y = 1
Subs x.x for y
x.x = 16/9 or x.x = 1
taking square root we get x = 4/3 or x = 1