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-26x^{2}=-312
Subtract 312 from both sides. Anything subtracted from zero gives its negation.
x^{2}=\frac{-312}{-26}
Divide both sides by -26.
x^{2}=12
Divide -312 by -26 to get 12.
x=2\sqrt{3} x=-2\sqrt{3}
Take the square root of both sides of the equation.
-26x^{2}+312=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\left(-26\right)\times 312}}{2\left(-26\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -26 for a, 0 for b, and 312 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\left(-26\right)\times 312}}{2\left(-26\right)}
Square 0.
x=\frac{0±\sqrt{104\times 312}}{2\left(-26\right)}
Multiply -4 times -26.
x=\frac{0±\sqrt{32448}}{2\left(-26\right)}
Multiply 104 times 312.
x=\frac{0±104\sqrt{3}}{2\left(-26\right)}
Take the square root of 32448.
x=\frac{0±104\sqrt{3}}{-52}
Multiply 2 times -26.
x=-2\sqrt{3}
Now solve the equation x=\frac{0±104\sqrt{3}}{-52} when ± is plus.
x=2\sqrt{3}
Now solve the equation x=\frac{0±104\sqrt{3}}{-52} when ± is minus.
x=-2\sqrt{3} x=2\sqrt{3}
The equation is now solved.