Solve for x
x=4
x=-4
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48-3x^{2}=0
Swap sides so that all variable terms are on the left hand side.
-3x^{2}=-48
Subtract 48 from both sides. Anything subtracted from zero gives its negation.
x^{2}=\frac{-48}{-3}
Divide both sides by -3.
x^{2}=16
Divide -48 by -3 to get 16.
x=4 x=-4
Take the square root of both sides of the equation.
48-3x^{2}=0
Swap sides so that all variable terms are on the left hand side.
-3x^{2}+48=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(-3\right)\times 48}}{2\left(-3\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -3 for a, 0 for b, and 48 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\left(-3\right)\times 48}}{2\left(-3\right)}
Square 0.
x=\frac{0±\sqrt{12\times 48}}{2\left(-3\right)}
Multiply -4 times -3.
x=\frac{0±\sqrt{576}}{2\left(-3\right)}
Multiply 12 times 48.
x=\frac{0±24}{2\left(-3\right)}
Take the square root of 576.
x=\frac{0±24}{-6}
Multiply 2 times -3.
x=-4
Now solve the equation x=\frac{0±24}{-6} when ± is plus. Divide 24 by -6.
x=4
Now solve the equation x=\frac{0±24}{-6} when ± is minus. Divide -24 by -6.
x=-4 x=4
The equation is now solved.
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