Solve for x
x=4
x=-4
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\left(\frac{1}{2}\right)^{2}x^{2}=4
Expand \left(\frac{1}{2}x\right)^{2}.
\frac{1}{4}x^{2}=4
Calculate \frac{1}{2} to the power of 2 and get \frac{1}{4}.
\frac{1}{4}x^{2}-4=0
Subtract 4 from both sides.
x^{2}-16=0
Multiply both sides by 4.
\left(x-4\right)\left(x+4\right)=0
Consider x^{2}-16. Rewrite x^{2}-16 as x^{2}-4^{2}. The difference of squares can be factored using the rule: a^{2}-b^{2}=\left(a-b\right)\left(a+b\right).
x=4 x=-4
To find equation solutions, solve x-4=0 and x+4=0.
\left(\frac{1}{2}\right)^{2}x^{2}=4
Expand \left(\frac{1}{2}x\right)^{2}.
\frac{1}{4}x^{2}=4
Calculate \frac{1}{2} to the power of 2 and get \frac{1}{4}.
x^{2}=4\times 4
Multiply both sides by 4, the reciprocal of \frac{1}{4}.
x^{2}=16
Multiply 4 and 4 to get 16.
x=4 x=-4
Take the square root of both sides of the equation.
\left(\frac{1}{2}\right)^{2}x^{2}=4
Expand \left(\frac{1}{2}x\right)^{2}.
\frac{1}{4}x^{2}=4
Calculate \frac{1}{2} to the power of 2 and get \frac{1}{4}.
\frac{1}{4}x^{2}-4=0
Subtract 4 from both sides.
x=\frac{0±\sqrt{0^{2}-4\times \frac{1}{4}\left(-4\right)}}{2\times \frac{1}{4}}
This equation is in standard form: ax^{2}+bx+c=0. Substitute \frac{1}{4} for a, 0 for b, and -4 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times \frac{1}{4}\left(-4\right)}}{2\times \frac{1}{4}}
Square 0.
x=\frac{0±\sqrt{-\left(-4\right)}}{2\times \frac{1}{4}}
Multiply -4 times \frac{1}{4}.
x=\frac{0±\sqrt{4}}{2\times \frac{1}{4}}
Multiply -1 times -4.
x=\frac{0±2}{2\times \frac{1}{4}}
Take the square root of 4.
x=\frac{0±2}{\frac{1}{2}}
Multiply 2 times \frac{1}{4}.
x=4
Now solve the equation x=\frac{0±2}{\frac{1}{2}} when ± is plus. Divide 2 by \frac{1}{2} by multiplying 2 by the reciprocal of \frac{1}{2}.
x=-4
Now solve the equation x=\frac{0±2}{\frac{1}{2}} when ± is minus. Divide -2 by \frac{1}{2} by multiplying -2 by the reciprocal of \frac{1}{2}.
x=4 x=-4
The equation is now solved.
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