Solve for x
x=2\sqrt{2}\approx 2.828427125
x=-2\sqrt{2}\approx -2.828427125
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\left(\frac{1}{2}\right)^{2}x^{2}+6=x^{2}
Expand \left(\frac{1}{2}x\right)^{2}.
\frac{1}{4}x^{2}+6=x^{2}
Calculate \frac{1}{2} to the power of 2 and get \frac{1}{4}.
\frac{1}{4}x^{2}+6-x^{2}=0
Subtract x^{2} from both sides.
-\frac{3}{4}x^{2}+6=0
Combine \frac{1}{4}x^{2} and -x^{2} to get -\frac{3}{4}x^{2}.
-\frac{3}{4}x^{2}=-6
Subtract 6 from both sides. Anything subtracted from zero gives its negation.
x^{2}=-6\left(-\frac{4}{3}\right)
Multiply both sides by -\frac{4}{3}, the reciprocal of -\frac{3}{4}.
x^{2}=8
Multiply -6 and -\frac{4}{3} to get 8.
x=2\sqrt{2} x=-2\sqrt{2}
Take the square root of both sides of the equation.
\left(\frac{1}{2}\right)^{2}x^{2}+6=x^{2}
Expand \left(\frac{1}{2}x\right)^{2}.
\frac{1}{4}x^{2}+6=x^{2}
Calculate \frac{1}{2} to the power of 2 and get \frac{1}{4}.
\frac{1}{4}x^{2}+6-x^{2}=0
Subtract x^{2} from both sides.
-\frac{3}{4}x^{2}+6=0
Combine \frac{1}{4}x^{2} and -x^{2} to get -\frac{3}{4}x^{2}.
x=\frac{0±\sqrt{0^{2}-4\left(-\frac{3}{4}\right)\times 6}}{2\left(-\frac{3}{4}\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -\frac{3}{4} for a, 0 for b, and 6 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\left(-\frac{3}{4}\right)\times 6}}{2\left(-\frac{3}{4}\right)}
Square 0.
x=\frac{0±\sqrt{3\times 6}}{2\left(-\frac{3}{4}\right)}
Multiply -4 times -\frac{3}{4}.
x=\frac{0±\sqrt{18}}{2\left(-\frac{3}{4}\right)}
Multiply 3 times 6.
x=\frac{0±3\sqrt{2}}{2\left(-\frac{3}{4}\right)}
Take the square root of 18.
x=\frac{0±3\sqrt{2}}{-\frac{3}{2}}
Multiply 2 times -\frac{3}{4}.
x=-2\sqrt{2}
Now solve the equation x=\frac{0±3\sqrt{2}}{-\frac{3}{2}} when ± is plus.
x=2\sqrt{2}
Now solve the equation x=\frac{0±3\sqrt{2}}{-\frac{3}{2}} when ± is minus.
x=-2\sqrt{2} x=2\sqrt{2}
The equation is now solved.
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