Solve for x
x=-\frac{1}{9}\approx -0.111111111
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x^{2}+2x+1=x^{2}-7x
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(x+1\right)^{2}.
x^{2}+2x+1-x^{2}=-7x
Subtract x^{2} from both sides.
2x+1=-7x
Combine x^{2} and -x^{2} to get 0.
2x+1+7x=0
Add 7x to both sides.
9x+1=0
Combine 2x and 7x to get 9x.
9x=-1
Subtract 1 from both sides. Anything subtracted from zero gives its negation.
x=\frac{-1}{9}
Divide both sides by 9.
x=-\frac{1}{9}
Fraction \frac{-1}{9} can be rewritten as -\frac{1}{9} by extracting the negative sign.
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