Solve for x
x=12
x=-12
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3x^{2}\times \frac{1}{4}=108
Multiply x and x to get x^{2}.
\frac{3}{4}x^{2}=108
Multiply 3 and \frac{1}{4} to get \frac{3}{4}.
x^{2}=108\times \frac{4}{3}
Multiply both sides by \frac{4}{3}, the reciprocal of \frac{3}{4}.
x^{2}=\frac{108\times 4}{3}
Express 108\times \frac{4}{3} as a single fraction.
x^{2}=\frac{432}{3}
Multiply 108 and 4 to get 432.
x^{2}=144
Divide 432 by 3 to get 144.
x=12 x=-12
Take the square root of both sides of the equation.
3x^{2}\times \frac{1}{4}=108
Multiply x and x to get x^{2}.
\frac{3}{4}x^{2}=108
Multiply 3 and \frac{1}{4} to get \frac{3}{4}.
\frac{3}{4}x^{2}-108=0
Subtract 108 from both sides.
x=\frac{0±\sqrt{0^{2}-4\times \frac{3}{4}\left(-108\right)}}{2\times \frac{3}{4}}
This equation is in standard form: ax^{2}+bx+c=0. Substitute \frac{3}{4} 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 \frac{3}{4}\left(-108\right)}}{2\times \frac{3}{4}}
Square 0.
x=\frac{0±\sqrt{-3\left(-108\right)}}{2\times \frac{3}{4}}
Multiply -4 times \frac{3}{4}.
x=\frac{0±\sqrt{324}}{2\times \frac{3}{4}}
Multiply -3 times -108.
x=\frac{0±18}{2\times \frac{3}{4}}
Take the square root of 324.
x=\frac{0±18}{\frac{3}{2}}
Multiply 2 times \frac{3}{4}.
x=12
Now solve the equation x=\frac{0±18}{\frac{3}{2}} when ± is plus. Divide 18 by \frac{3}{2} by multiplying 18 by the reciprocal of \frac{3}{2}.
x=-12
Now solve the equation x=\frac{0±18}{\frac{3}{2}} when ± is minus. Divide -18 by \frac{3}{2} by multiplying -18 by the reciprocal of \frac{3}{2}.
x=12 x=-12
The equation is now solved.
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