SOLUTION: If x = 2 is one solution of x^2 + 8x - c = 0, then the other solution is… (A)20 (B) 10 (C) - 2 (D) - 10 (E) - 20

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Question 339048: If x = 2 is one solution of x^2 + 8x - c = 0, then the other solution is…
(A)20 (B) 10 (C) - 2 (D) - 10 (E) - 20
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
If x = 2 is one solution of x^2 + 8x - c = 0, then the other solution is…
(A)20 (B) 10 (C) - 2 (D) - 10 (E) - 20
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Use synthetic division:
2)....1....8....-c
.......1....10...|..-c+20
Solve -c+20 = 0
c = 20
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Now solve x^2+8x-20 = 0
Factor:
(x+10)(x-2)=0
x = -10 or x = 2
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Cheers,
Stan H.