Solve x^2-(x+7)^2=161

$$x ^ { 2 } - ( x + 7 ) ^ { 2 } = 161$$

Solve for x

$$x=-15$$

Steps for Solving Linear Equation

Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(x+7\right)^{2}.

$$x^{2}-\left(x^{2}+14x+49\right)=161$$

To find the opposite of x^{2}+14x+49, find the opposite of each term.

$$x^{2}-x^{2}-14x-49=161$$

Combine x^{2} and -x^{2} to get 0.

$$-14x-49=161$$

Add 49 to both sides.

$$-14x=161+49$$

Add 161 and 49 to get 210.

$$-14x=210$$

Divide both sides by -14.

$$x=\frac{210}{-14}$$

Divide 210 by -14 to get -15.

$$x=-15$$