SOLUTION: {{{x^2+7x=18}}}

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Question 324550: x%5E2%2B7x=18

Found 2 solutions by katealdridge, mananth:
Answer by katealdridge(100) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2%2B7x=18 first-subtract 18 from both sides
x%5E2%2B7x-18=0 then factor-look for 2 numbers that mult to -18 and add or subtract to get +7. They are +9 and -2.
%28x%2B9%29%28x-2%29=0 then set each factor equal to zero
%28x%2B9%29=0+and+%28x-2%29=0 finally, solve each equation (sub 9 from both sides, add 2 to both sides)
x=-9+and+x=2
to check, substitute -9 for x and 2 for x.
%28-9%29%5E2%2B7%28-9%29=18
81-63=18
%282%29%5E2%2B7%282%29=18
4%2B14=18

Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
x^2+7x= 18
add -18 to both sides
x^2+7x-18=18-18
x^2+7x-18=0
x^2+9x-2x-18=0
x(x+9)-2(x+9)=0
(x+9)(x-2)=0
x=-9 OR x=2