Solve for x
x=12
x=-12
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x^{2}-144=0
Divide both sides by 2.
\left(x-12\right)\left(x+12\right)=0
Consider x^{2}-144. Rewrite x^{2}-144 as x^{2}-12^{2}. The difference of squares can be factored using the rule: a^{2}-b^{2}=\left(a-b\right)\left(a+b\right).
x=12 x=-12
To find equation solutions, solve x-12=0 and x+12=0.
2x^{2}=288
Add 288 to both sides. Anything plus zero gives itself.
x^{2}=\frac{288}{2}
Divide both sides by 2.
x^{2}=144
Divide 288 by 2 to get 144.
x=12 x=-12
Take the square root of both sides of the equation.
2x^{2}-288=0
Quadratic equations like this one, with an x^{2} term but no x term, can still be solved using the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}, once they are put in standard form: ax^{2}+bx+c=0.
x=\frac{0±\sqrt{0^{2}-4\times 2\left(-288\right)}}{2\times 2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 2 for a, 0 for b, and -288 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times 2\left(-288\right)}}{2\times 2}
Square 0.
x=\frac{0±\sqrt{-8\left(-288\right)}}{2\times 2}
Multiply -4 times 2.
x=\frac{0±\sqrt{2304}}{2\times 2}
Multiply -8 times -288.
x=\frac{0±48}{2\times 2}
Take the square root of 2304.
x=\frac{0±48}{4}
Multiply 2 times 2.
x=12
Now solve the equation x=\frac{0±48}{4} when ± is plus. Divide 48 by 4.
x=-12
Now solve the equation x=\frac{0±48}{4} when ± is minus. Divide -48 by 4.
x=12 x=-12
The equation is now solved.
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