Solve for x
x=-7
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x^{2}+14x+49=\left(x+7\right)\left(x-7\right)
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(x+7\right)^{2}.
x^{2}+14x+49=x^{2}-49
Consider \left(x+7\right)\left(x-7\right). Multiplication can be transformed into difference of squares using the rule: \left(a-b\right)\left(a+b\right)=a^{2}-b^{2}. Square 7.
x^{2}+14x+49-x^{2}=-49
Subtract x^{2} from both sides.
14x+49=-49
Combine x^{2} and -x^{2} to get 0.
14x=-49-49
Subtract 49 from both sides.
14x=-98
Subtract 49 from -49 to get -98.
x=\frac{-98}{14}
Divide both sides by 14.
x=-7
Divide -98 by 14 to get -7.
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