Solve for x
x=10\sqrt{10}\approx 31.622776602
x=-10\sqrt{10}\approx -31.622776602
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-30x^{2}=-30000
Subtract 30000 from both sides. Anything subtracted from zero gives its negation.
x^{2}=\frac{-30000}{-30}
Divide both sides by -30.
x^{2}=1000
Divide -30000 by -30 to get 1000.
x=10\sqrt{10} x=-10\sqrt{10}
Take the square root of both sides of the equation.
-30x^{2}+30000=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\left(-30\right)\times 30000}}{2\left(-30\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -30 for a, 0 for b, and 30000 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\left(-30\right)\times 30000}}{2\left(-30\right)}
Square 0.
x=\frac{0±\sqrt{120\times 30000}}{2\left(-30\right)}
Multiply -4 times -30.
x=\frac{0±\sqrt{3600000}}{2\left(-30\right)}
Multiply 120 times 30000.
x=\frac{0±600\sqrt{10}}{2\left(-30\right)}
Take the square root of 3600000.
x=\frac{0±600\sqrt{10}}{-60}
Multiply 2 times -30.
x=-10\sqrt{10}
Now solve the equation x=\frac{0±600\sqrt{10}}{-60} when ± is plus.
x=10\sqrt{10}
Now solve the equation x=\frac{0±600\sqrt{10}}{-60} when ± is minus.
x=-10\sqrt{10} x=10\sqrt{10}
The equation is now solved.
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