Solve for x
x = \frac{\sqrt{286}}{2} \approx 8.455767263
x = -\frac{\sqrt{286}}{2} \approx -8.455767263
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2x^{2}-13=130
Combine x^{2} and x^{2} to get 2x^{2}.
2x^{2}=130+13
Add 13 to both sides.
2x^{2}=143
Add 130 and 13 to get 143.
x^{2}=\frac{143}{2}
Divide both sides by 2.
x=\frac{\sqrt{286}}{2} x=-\frac{\sqrt{286}}{2}
Take the square root of both sides of the equation.
2x^{2}-13=130
Combine x^{2} and x^{2} to get 2x^{2}.
2x^{2}-13-130=0
Subtract 130 from both sides.
2x^{2}-143=0
Subtract 130 from -13 to get -143.
x=\frac{0±\sqrt{0^{2}-4\times 2\left(-143\right)}}{2\times 2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 2 for a, 0 for b, and -143 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times 2\left(-143\right)}}{2\times 2}
Square 0.
x=\frac{0±\sqrt{-8\left(-143\right)}}{2\times 2}
Multiply -4 times 2.
x=\frac{0±\sqrt{1144}}{2\times 2}
Multiply -8 times -143.
x=\frac{0±2\sqrt{286}}{2\times 2}
Take the square root of 1144.
x=\frac{0±2\sqrt{286}}{4}
Multiply 2 times 2.
x=\frac{\sqrt{286}}{2}
Now solve the equation x=\frac{0±2\sqrt{286}}{4} when ± is plus.
x=-\frac{\sqrt{286}}{2}
Now solve the equation x=\frac{0±2\sqrt{286}}{4} when ± is minus.
x=\frac{\sqrt{286}}{2} x=-\frac{\sqrt{286}}{2}
The equation is now solved.
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