SOLUTION: One roots of the equation x^3 - 2x^2 – 13x - 10 = 0 is 5. What is the sum of its other roots? (a)-2 (b) -3 (c) 2 (d) 1 (e) None of these

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Question 289860: One roots of the equation x^3 - 2x^2 – 13x - 10 = 0 is 5. What is the sum of its other roots?
(a)-2 (b) -3 (c) 2 (d) 1 (e) None of these

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
One root of the equation x^3 - 2x^2 – 13x - 10 = 0 is 5. What is the sum of its other roots?
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Use synthetic division:
5)....1....-2....-13....-10
......1.....3.....2....|..0
Quotient: x^2 + 3x + 2
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Solve x^2 + 3x + 2 = 0
Factor: (x+2)(x+1) = 0
x = -1 or x = -2
Sum = -3
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Cheers,
Stan H.
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(a)-2 (b) -3 (c) 2 (d) 1 (e) None of these