Solve for x
x = \frac{6 \sqrt{15}}{5} \approx 4.647580015
x = -\frac{6 \sqrt{15}}{5} \approx -4.647580015
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5x^{2}=54\times 2
Multiply both sides by 2.
5x^{2}=108
Multiply 54 and 2 to get 108.
x^{2}=\frac{108}{5}
Divide both sides by 5.
x=\frac{6\sqrt{15}}{5} x=-\frac{6\sqrt{15}}{5}
Take the square root of both sides of the equation.
5x^{2}=54\times 2
Multiply both sides by 2.
5x^{2}=108
Multiply 54 and 2 to get 108.
5x^{2}-108=0
Subtract 108 from both sides.
x=\frac{0±\sqrt{0^{2}-4\times 5\left(-108\right)}}{2\times 5}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 5 for a, 0 for b, and -108 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times 5\left(-108\right)}}{2\times 5}
Square 0.
x=\frac{0±\sqrt{-20\left(-108\right)}}{2\times 5}
Multiply -4 times 5.
x=\frac{0±\sqrt{2160}}{2\times 5}
Multiply -20 times -108.
x=\frac{0±12\sqrt{15}}{2\times 5}
Take the square root of 2160.
x=\frac{0±12\sqrt{15}}{10}
Multiply 2 times 5.
x=\frac{6\sqrt{15}}{5}
Now solve the equation x=\frac{0±12\sqrt{15}}{10} when ± is plus.
x=-\frac{6\sqrt{15}}{5}
Now solve the equation x=\frac{0±12\sqrt{15}}{10} when ± is minus.
x=\frac{6\sqrt{15}}{5} x=-\frac{6\sqrt{15}}{5}
The equation is now solved.
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