SOLUTION: Find all real or imaginary solutions. Sqrt(2x^2+x-12)=x

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Question 167824: Find all real or imaginary solutions.
Sqrt(2x^2+x-12)=x
Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
Sqrt(2x^2+x-12)=x squaring both sides we get:
2x^2+x-12=x^2
2x^2-x^2+x-12=0
x^2+x-12=0
(x+4)(x-3)
x+4=0
x=-4 ans.
x-3
x=3 ans.
Proofs:
sqrt(2*-4^2+(-4)-12=-4
sqrt(2*16-4-12)=-4
sqrt(32-16)=-4
sqrt16=-4
-4=-4
sqrt(2*3^2+3-12)=3
sqrt(2*9+3-12)=3
sqrt(18+3-12)=3
sqrt9=3
3=3