SOLUTION: Solve the following quadratic equation (x-5)(x+2)=18 Thank you for your help

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Question 105096: Solve the following quadratic equation
(x-5)(x+2)=18
Thank you for your help
Answer by HyperBrain(694) About Me  (Show Source):
You can put this solution on YOUR website!
%28x-5%29%28x%2B2%29=18
%28x-5%29%28x%2B2%29=x%28x%2B2%29-5%28x%2B2%29
%28x-5%29%28x%2B2%29=%28x%5E2%2B2x%29-%285x%2B10%29
%28x-5%29%28x%2B2%29=x%5E2%2B%282x-5x%29%2B10
%28x-5%29%28x%2B2%29=x%5E2-3x%2B10
So,
x%5E2-3x%2B10=18
x%5E2-3x%2B10-18=18-18
x%5E2-3x-8=0
Using the quadratic formula,
x=%283%2B-sqrt%283%5E2-4%2A1%2A%28-8%29%29%29%2F%282%2A1%29
x=%283%2B-sqrt%289%2B32%29%29%2F%282%29
x=%283%2Bsqrt%2841%29%29%2F%282%29 or x=%283-sqrt%2841%29%29%2F%282%29
Power up,
HyperBrain!