SOLUTION: factor x^2-3x-18

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Question 71321: factor x^2-3x-18
Answer by galactus(183) About Me  (Show Source):
You can put this solution on YOUR website!
Find two numbers when added equal -3 and when multiplied equal -18
a%2Bb=-3
ab=-18
Solving we find -6 and 3. (-6)(3)=-18 and -6+3=-3.
x%5E2-6x%2B3x-18=0
Group:
%28x%5E2-6x%29%2B%283x-18%29
Factor out a common factor:
x%28x-6%29%2B3%28x-6%29
%28x-6%29%28x%2B3%29