Question 337166: please help me solve this equation:x to the third power +4x square-3x-12 Found 2 solutions by nerdybill, stanbon:Answer by nerdybill(7384) (Show Source):
You can put this solution on YOUR website! please help me solve this equation:x to the third power +4x square-3x-12
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You don't really "solve" the equation, rather, you can "fator" it.
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Group terms: Notice the sign flipped.
Factor each group:
You can put this solution on YOUR website! x to the third power +4x square-3x-12
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x^3+4x^2-3x-12 = 0
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I graphed it and found a zero at x = -4
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Then I used synthetic division:
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-4)....1....4....-3....-12
........1.....0....-3...|..0
Quotient: x^2-3 = 0
Factor:(x-sqrt(3))(x+sqrt(3)) = 0
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Solutions: x = -4 or x = sqrt(3) or x = -sqrt(3)
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Cheers,
Stan H.
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