SOLUTION: how do I solve {{{x^2-7x=18}}} while setting the equation to 0 first?

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Question 1010018: how do I solve x%5E2-7x=18 while setting the equation to 0 first?
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

x%5E2-7x=18.......move 18 to the left
x%5E2-7x-18=0....factor completely; first write -7x as 2x-9x
x%5E2%2B2x-9x-18=0.........group
%28x%5E2%2B2x%29-%289x%2B18%29=0...factor out x from first group and 9 from second group
x%28x%2B2%29-9%28x%2B2%29=0...factor out x%2B2
%28x-9%29%28x%2B2%29=0
solutions:
if %28x-9%29=0=>highlight%28x=9%29
if %28x%2B2%29=0=>highlight%28x=-2%29