Solve for x (complex solution)
x=-3i
x=3i
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3\times 3=-\frac{1}{3}x\times 3x
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 3x, the least common multiple of x,3.
9=-\frac{1}{3}x\times 3x
Multiply 3 and 3 to get 9.
9=-\frac{1}{3}x^{2}\times 3
Multiply x and x to get x^{2}.
9=-x^{2}
Cancel out 3 and 3.
-x^{2}=9
Swap sides so that all variable terms are on the left hand side.
x^{2}=-9
Divide both sides by -1.
x=3i x=-3i
The equation is now solved.
3\times 3=-\frac{1}{3}x\times 3x
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 3x, the least common multiple of x,3.
9=-\frac{1}{3}x\times 3x
Multiply 3 and 3 to get 9.
9=-\frac{1}{3}x^{2}\times 3
Multiply x and x to get x^{2}.
9=-x^{2}
Cancel out 3 and 3.
-x^{2}=9
Swap sides so that all variable terms are on the left hand side.
-x^{2}-9=0
Subtract 9 from both sides.
x=\frac{0±\sqrt{0^{2}-4\left(-1\right)\left(-9\right)}}{2\left(-1\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -1 for a, 0 for b, and -9 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\left(-1\right)\left(-9\right)}}{2\left(-1\right)}
Square 0.
x=\frac{0±\sqrt{4\left(-9\right)}}{2\left(-1\right)}
Multiply -4 times -1.
x=\frac{0±\sqrt{-36}}{2\left(-1\right)}
Multiply 4 times -9.
x=\frac{0±6i}{2\left(-1\right)}
Take the square root of -36.
x=\frac{0±6i}{-2}
Multiply 2 times -1.
x=-3i
Now solve the equation x=\frac{0±6i}{-2} when ± is plus.
x=3i
Now solve the equation x=\frac{0±6i}{-2} when ± is minus.
x=-3i x=3i
The equation is now solved.
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