Solve for x
x=3\sqrt{3}\approx 5.196152423
x=-3\sqrt{3}\approx -5.196152423
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27x^{2}=729
Calculate 27 to the power of 2 and get 729.
x^{2}=\frac{729}{27}
Divide both sides by 27.
x^{2}=27
Divide 729 by 27 to get 27.
x=3\sqrt{3} x=-3\sqrt{3}
Take the square root of both sides of the equation.
27x^{2}=729
Calculate 27 to the power of 2 and get 729.
27x^{2}-729=0
Subtract 729 from both sides.
x=\frac{0±\sqrt{0^{2}-4\times 27\left(-729\right)}}{2\times 27}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 27 for a, 0 for b, and -729 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times 27\left(-729\right)}}{2\times 27}
Square 0.
x=\frac{0±\sqrt{-108\left(-729\right)}}{2\times 27}
Multiply -4 times 27.
x=\frac{0±\sqrt{78732}}{2\times 27}
Multiply -108 times -729.
x=\frac{0±162\sqrt{3}}{2\times 27}
Take the square root of 78732.
x=\frac{0±162\sqrt{3}}{54}
Multiply 2 times 27.
x=3\sqrt{3}
Now solve the equation x=\frac{0±162\sqrt{3}}{54} when ± is plus.
x=-3\sqrt{3}
Now solve the equation x=\frac{0±162\sqrt{3}}{54} when ± is minus.
x=3\sqrt{3} x=-3\sqrt{3}
The equation is now solved.
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