Solve for x
x=2\sqrt{2}\approx 2.828427125
x=-2\sqrt{2}\approx -2.828427125
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x^{2}=\frac{16}{2}
Divide both sides by 2.
x^{2}=8
Divide 16 by 2 to get 8.
x=2\sqrt{2} x=-2\sqrt{2}
Take the square root of both sides of the equation.
x^{2}=\frac{16}{2}
Divide both sides by 2.
x^{2}=8
Divide 16 by 2 to get 8.
x^{2}-8=0
Subtract 8 from both sides.
x=\frac{0±\sqrt{0^{2}-4\left(-8\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 0 for b, and -8 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\left(-8\right)}}{2}
Square 0.
x=\frac{0±\sqrt{32}}{2}
Multiply -4 times -8.
x=\frac{0±4\sqrt{2}}{2}
Take the square root of 32.
x=2\sqrt{2}
Now solve the equation x=\frac{0±4\sqrt{2}}{2} when ± is plus.
x=-2\sqrt{2}
Now solve the equation x=\frac{0±4\sqrt{2}}{2} when ± is minus.
x=2\sqrt{2} x=-2\sqrt{2}
The equation is now solved.
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