SOLUTION: Can you help me solve for real roots? 2x^8+15x^4=27

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Question 766857: Can you help me solve for real roots?
2x^8+15x^4=27
Answer by tommyt3rd(5050) About Me  (Show Source):
You can put this solution on YOUR website!
u=x^4
2u^2+15u-27=0
2u^2+18u-3u-27=0
2u(u+9)-3(u+9)=0
(2u-3)(u+9)=0

but u+9 contributes no real roots

2u-3=0
u=3/2

x^4 = 3/2

x^2 = +- sqrt(3/2)

from which we use the principal root

thus
%0D%0Ax=++root%284%2C3%2F2%29%0D%0A
or
%0D%0Ax=+-+root%284%2C3%2F2%29%0D%0A