Solve for x
x=4
x=-4
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2x^{2}+30-62=0
Subtract 62 from both sides.
2x^{2}-32=0
Subtract 62 from 30 to get -32.
x^{2}-16=0
Divide both sides by 2.
\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.
2x^{2}=62-30
Subtract 30 from both sides.
2x^{2}=32
Subtract 30 from 62 to get 32.
x^{2}=\frac{32}{2}
Divide both sides by 2.
x^{2}=16
Divide 32 by 2 to get 16.
x=4 x=-4
Take the square root of both sides of the equation.
2x^{2}+30-62=0
Subtract 62 from both sides.
2x^{2}-32=0
Subtract 62 from 30 to get -32.
x=\frac{0±\sqrt{0^{2}-4\times 2\left(-32\right)}}{2\times 2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 2 for a, 0 for b, and -32 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times 2\left(-32\right)}}{2\times 2}
Square 0.
x=\frac{0±\sqrt{-8\left(-32\right)}}{2\times 2}
Multiply -4 times 2.
x=\frac{0±\sqrt{256}}{2\times 2}
Multiply -8 times -32.
x=\frac{0±16}{2\times 2}
Take the square root of 256.
x=\frac{0±16}{4}
Multiply 2 times 2.
x=4
Now solve the equation x=\frac{0±16}{4} when ± is plus. Divide 16 by 4.
x=-4
Now solve the equation x=\frac{0±16}{4} when ± is minus. Divide -16 by 4.
x=4 x=-4
The equation is now solved.
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