Solve for x
x=6
x=-6
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x^{2}+2x-36-2x=0
Subtract 2x from both sides.
x^{2}-36=0
Combine 2x and -2x to get 0.
\left(x-6\right)\left(x+6\right)=0
Consider x^{2}-36. Rewrite x^{2}-36 as x^{2}-6^{2}. The difference of squares can be factored using the rule: a^{2}-b^{2}=\left(a-b\right)\left(a+b\right).
x=6 x=-6
To find equation solutions, solve x-6=0 and x+6=0.
x^{2}+2x-36-2x=0
Subtract 2x from both sides.
x^{2}-36=0
Combine 2x and -2x to get 0.
x^{2}=36
Add 36 to both sides. Anything plus zero gives itself.
x=6 x=-6
Take the square root of both sides of the equation.
x^{2}+2x-36-2x=0
Subtract 2x from both sides.
x^{2}-36=0
Combine 2x and -2x to get 0.
x=\frac{0±\sqrt{0^{2}-4\left(-36\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 0 for b, and -36 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\left(-36\right)}}{2}
Square 0.
x=\frac{0±\sqrt{144}}{2}
Multiply -4 times -36.
x=\frac{0±12}{2}
Take the square root of 144.
x=6
Now solve the equation x=\frac{0±12}{2} when ± is plus. Divide 12 by 2.
x=-6
Now solve the equation x=\frac{0±12}{2} when ± is minus. Divide -12 by 2.
x=6 x=-6
The equation is now solved.
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