Solve for x
x=4
x=0
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-2\sqrt{9x}=-3x
Subtract 3x from both sides of the equation.
\left(-2\sqrt{9x}\right)^{2}=\left(-3x\right)^{2}
Square both sides of the equation.
\left(-2\right)^{2}\left(\sqrt{9x}\right)^{2}=\left(-3x\right)^{2}
Expand \left(-2\sqrt{9x}\right)^{2}.
4\left(\sqrt{9x}\right)^{2}=\left(-3x\right)^{2}
Calculate -2 to the power of 2 and get 4.
4\times 9x=\left(-3x\right)^{2}
Calculate \sqrt{9x} to the power of 2 and get 9x.
36x=\left(-3x\right)^{2}
Multiply 4 and 9 to get 36.
36x=\left(-3\right)^{2}x^{2}
Expand \left(-3x\right)^{2}.
36x=9x^{2}
Calculate -3 to the power of 2 and get 9.
36x-9x^{2}=0
Subtract 9x^{2} from both sides.
x\left(36-9x\right)=0
Factor out x.
x=0 x=4
To find equation solutions, solve x=0 and 36-9x=0.
3\times 0-2\sqrt{9\times 0}=0
Substitute 0 for x in the equation 3x-2\sqrt{9x}=0.
0=0
Simplify. The value x=0 satisfies the equation.
3\times 4-2\sqrt{9\times 4}=0
Substitute 4 for x in the equation 3x-2\sqrt{9x}=0.
0=0
Simplify. The value x=4 satisfies the equation.
x=0 x=4
List all solutions of -2\sqrt{9x}=-3x.
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