Solve for x
x = \frac{\sqrt{14}}{3} \approx 1.247219129
x = -\frac{\sqrt{14}}{3} \approx -1.247219129
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\frac{1}{2}x^{2}\times 9=7
Calculate 3 to the power of 2 and get 9.
\frac{9}{2}x^{2}=7
Multiply \frac{1}{2} and 9 to get \frac{9}{2}.
x^{2}=7\times \frac{2}{9}
Multiply both sides by \frac{2}{9}, the reciprocal of \frac{9}{2}.
x^{2}=\frac{14}{9}
Multiply 7 and \frac{2}{9} to get \frac{14}{9}.
x=\frac{\sqrt{14}}{3} x=-\frac{\sqrt{14}}{3}
Take the square root of both sides of the equation.
\frac{1}{2}x^{2}\times 9=7
Calculate 3 to the power of 2 and get 9.
\frac{9}{2}x^{2}=7
Multiply \frac{1}{2} and 9 to get \frac{9}{2}.
\frac{9}{2}x^{2}-7=0
Subtract 7 from both sides.
x=\frac{0±\sqrt{0^{2}-4\times \frac{9}{2}\left(-7\right)}}{2\times \frac{9}{2}}
This equation is in standard form: ax^{2}+bx+c=0. Substitute \frac{9}{2} for a, 0 for b, and -7 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times \frac{9}{2}\left(-7\right)}}{2\times \frac{9}{2}}
Square 0.
x=\frac{0±\sqrt{-18\left(-7\right)}}{2\times \frac{9}{2}}
Multiply -4 times \frac{9}{2}.
x=\frac{0±\sqrt{126}}{2\times \frac{9}{2}}
Multiply -18 times -7.
x=\frac{0±3\sqrt{14}}{2\times \frac{9}{2}}
Take the square root of 126.
x=\frac{0±3\sqrt{14}}{9}
Multiply 2 times \frac{9}{2}.
x=\frac{\sqrt{14}}{3}
Now solve the equation x=\frac{0±3\sqrt{14}}{9} when ± is plus.
x=-\frac{\sqrt{14}}{3}
Now solve the equation x=\frac{0±3\sqrt{14}}{9} when ± is minus.
x=\frac{\sqrt{14}}{3} x=-\frac{\sqrt{14}}{3}
The equation is now solved.
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Limits
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