SOLUTION: What are factors of -12 that when added together equal to -1

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Question 799080: What are factors of -12 that when added together equal to -1
Found 2 solutions by stanbon, Finavon:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
What are factors of -12 that when added together equal to -1
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Answer: -4 and 3
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Cheers,
Stan H.
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Answer by Finavon(81) About Me  (Show Source):
You can put this solution on YOUR website!
factors (integers) a and b
a+b=-1 (1)
a*b=-12 (2)
rearrange (1) a=-(1+b)
subst for a in (2):
-(1+b)*b=-12
+-b-b%5E2+=+-12+
rearrange b%5E2%2Bb-12=0+
solves for +%28-1+%2B-sqrt%281%2B4%2A12%29%29%2F2+
+%28-1+%2B-+7%29%2F2+=+3+or+-4
Factors are 3 and -4