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5x^{2}-13=0
All equations of the form ax^{2}+bx+c=0 can be solved using the quadratic formula: \frac{-b±\sqrt{b^{2}-4ac}}{2a}. The quadratic formula gives two solutions, one when ± is addition and one when it is subtraction.
x=\frac{0±\sqrt{0^{2}-4\times 5\left(-13\right)}}{2\times 5}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 5 for a, 0 for b, and -13 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times 5\left(-13\right)}}{2\times 5}
Square 0.
x=\frac{0±\sqrt{-20\left(-13\right)}}{2\times 5}
Multiply -4 times 5.
x=\frac{0±\sqrt{260}}{2\times 5}
Multiply -20 times -13.
x=\frac{0±2\sqrt{65}}{2\times 5}
Take the square root of 260.
x=\frac{0±2\sqrt{65}}{10}
Multiply 2 times 5.
x=\frac{\sqrt{65}}{5}
Now solve the equation x=\frac{0±2\sqrt{65}}{10} when ± is plus.
x=-\frac{\sqrt{65}}{5}
Now solve the equation x=\frac{0±2\sqrt{65}}{10} when ± is minus.
x=\frac{\sqrt{65}}{5} x=-\frac{\sqrt{65}}{5}
The equation is now solved.