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2x^{2}-4=0
Subtract 1 from -3 to get -4.
2x^{2}=4
Add 4 to both sides. Anything plus zero gives itself.
x^{2}=\frac{4}{2}
Divide both sides by 2.
x^{2}=2
Divide 4 by 2 to get 2.
x=\sqrt{2} x=-\sqrt{2}
Take the square root of both sides of the equation.
2x^{2}-4=0
Subtract 1 from -3 to get -4.
x=\frac{0±\sqrt{0^{2}-4\times 2\left(-4\right)}}{2\times 2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 2 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 2\left(-4\right)}}{2\times 2}
Square 0.
x=\frac{0±\sqrt{-8\left(-4\right)}}{2\times 2}
Multiply -4 times 2.
x=\frac{0±\sqrt{32}}{2\times 2}
Multiply -8 times -4.
x=\frac{0±4\sqrt{2}}{2\times 2}
Take the square root of 32.
x=\frac{0±4\sqrt{2}}{4}
Multiply 2 times 2.
x=\sqrt{2}
Now solve the equation x=\frac{0±4\sqrt{2}}{4} when ± is plus.
x=-\sqrt{2}
Now solve the equation x=\frac{0±4\sqrt{2}}{4} when ± is minus.
x=\sqrt{2} x=-\sqrt{2}
The equation is now solved.