SOLUTION: find the sum of the solutions of the following quadratic equation x2+9x-36

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Question 444323: find the sum of the solutions of the following quadratic equation x2+9x-36
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2%2B9x-36=0....factor it...replace 9x with -3x%2B12x
x%5E2-3x%2B12x-36=0.....group
%28x%5E2-3x%29%2B%2812x-36%29=0
x%28x-3%29%2B12%28x-3%29=0
%28x%2B12%29%28x-3%29=0
x%2B12=0 if x=-12
x-3=0 if x=+3

+graph%28+500%2C+500%2C+-24%2C+24%2C+-60%2C+25%2C+x%5E2%2B9x-36%29+