SOLUTION: Rational Root to x^3 + 2x^2 - 8x - 16 = 0

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Question 716766: Rational Root to x^3 + 2x^2 - 8x - 16 = 0
Found 2 solutions by lwsshak3, stanbon:
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
Rational Root to
x^3 + 2x^2 - 8x - 16 = 0
factor by grouping:
x^2(x+2)-8(x+2)=0
(x+2)(x^2-8)=0
x=-2
or
x=±√8

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Rational Root to x^3 + 2x^2 - 8x - 16 = 0
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Using synthetic division:
-2)....1....2....-8....-16
.......1....0....-8...|..0
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Find roots of the the quotient:
x^2 - 8 = 0
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x = 2sqrt(2) or x = -2sqrt(2) or x = -2
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Cheers,
Stan H.
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