You can put this solution on YOUR website! (2x^2+3x-1)^(2/3) = 4
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Raise both sides to the (3/2) power to get:
2x^2+3x-1 = 4^(3/2)
2x^2+3x-1 = 8
2x^2+3x-9 = 0
2x^2+6x-3x-9 = 0
2x(x+3)-3(x+3) = 0
(x+3)(2x-3) = 0
x = -3 or x = 3/2
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Cheers,
Stan H.