SOLUTION: How do you solve 12x^3 + 31x^2 - 17x - 6 = 0?

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Question 730875: How do you solve 12x^3 + 31x^2 - 17x - 6 = 0?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
How do you solve 12x^3 + 31x^2 - 17x - 6 = 0?
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I graphed it to find a zero at x = -3
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Use synthetic division to factor and find the other 2 zeroes.
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-3)....12....31.....-17....-6
.......12....-5.....-2...|..0
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Quotient: 12x^2 - 5x -2
Factor:
12x^2 -8x+3x -2 = 0
4x(3x-2) + (3x-2) = 0
(3x-2)(4x+1) = 0
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x = 2/3 or x = -1/4 or -3
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Cheers,
Stan H.