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9+x^{2}+x^{2}=14
Add x^{2} to both sides.
9+2x^{2}=14
Combine x^{2} and x^{2} to get 2x^{2}.
2x^{2}=14-9
Subtract 9 from both sides.
2x^{2}=5
Subtract 9 from 14 to get 5.
x^{2}=\frac{5}{2}
Divide both sides by 2.
x=\frac{\sqrt{10}}{2} x=-\frac{\sqrt{10}}{2}
Take the square root of both sides of the equation.
9+x^{2}-14=-x^{2}
Subtract 14 from both sides.
-5+x^{2}=-x^{2}
Subtract 14 from 9 to get -5.
-5+x^{2}+x^{2}=0
Add x^{2} to both sides.
-5+2x^{2}=0
Combine x^{2} and x^{2} to get 2x^{2}.
2x^{2}-5=0
Quadratic equations like this one, with an x^{2} term but no x term, can still be solved using the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}, once they are put in standard form: ax^{2}+bx+c=0.
x=\frac{0±\sqrt{0^{2}-4\times 2\left(-5\right)}}{2\times 2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 2 for a, 0 for b, and -5 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times 2\left(-5\right)}}{2\times 2}
Square 0.
x=\frac{0±\sqrt{-8\left(-5\right)}}{2\times 2}
Multiply -4 times 2.
x=\frac{0±\sqrt{40}}{2\times 2}
Multiply -8 times -5.
x=\frac{0±2\sqrt{10}}{2\times 2}
Take the square root of 40.
x=\frac{0±2\sqrt{10}}{4}
Multiply 2 times 2.
x=\frac{\sqrt{10}}{2}
Now solve the equation x=\frac{0±2\sqrt{10}}{4} when ± is plus.
x=-\frac{\sqrt{10}}{2}
Now solve the equation x=\frac{0±2\sqrt{10}}{4} when ± is minus.
x=\frac{\sqrt{10}}{2} x=-\frac{\sqrt{10}}{2}
The equation is now solved.