Solve for x
x=3\sqrt{2}\approx 4.242640687
x=-3\sqrt{2}\approx -4.242640687
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2x^{2}+3=25+14
Calculate 5 to the power of 2 and get 25.
2x^{2}+3=39
Add 25 and 14 to get 39.
2x^{2}=39-3
Subtract 3 from both sides.
2x^{2}=36
Subtract 3 from 39 to get 36.
x^{2}=\frac{36}{2}
Divide both sides by 2.
x^{2}=18
Divide 36 by 2 to get 18.
x=3\sqrt{2} x=-3\sqrt{2}
Take the square root of both sides of the equation.
2x^{2}+3=25+14
Calculate 5 to the power of 2 and get 25.
2x^{2}+3=39
Add 25 and 14 to get 39.
2x^{2}+3-39=0
Subtract 39 from both sides.
2x^{2}-36=0
Subtract 39 from 3 to get -36.
x=\frac{0±\sqrt{0^{2}-4\times 2\left(-36\right)}}{2\times 2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 2 for a, 0 for b, and -36 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times 2\left(-36\right)}}{2\times 2}
Square 0.
x=\frac{0±\sqrt{-8\left(-36\right)}}{2\times 2}
Multiply -4 times 2.
x=\frac{0±\sqrt{288}}{2\times 2}
Multiply -8 times -36.
x=\frac{0±12\sqrt{2}}{2\times 2}
Take the square root of 288.
x=\frac{0±12\sqrt{2}}{4}
Multiply 2 times 2.
x=3\sqrt{2}
Now solve the equation x=\frac{0±12\sqrt{2}}{4} when ± is plus.
x=-3\sqrt{2}
Now solve the equation x=\frac{0±12\sqrt{2}}{4} when ± is minus.
x=3\sqrt{2} x=-3\sqrt{2}
The equation is now solved.
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