Solve for x
x=0
x=\frac{9}{49}\approx 0.183673469
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-3\sqrt{x}=-7x
Subtract 7x from both sides of the equation.
\left(-3\sqrt{x}\right)^{2}=\left(-7x\right)^{2}
Square both sides of the equation.
\left(-3\right)^{2}\left(\sqrt{x}\right)^{2}=\left(-7x\right)^{2}
Expand \left(-3\sqrt{x}\right)^{2}.
9\left(\sqrt{x}\right)^{2}=\left(-7x\right)^{2}
Calculate -3 to the power of 2 and get 9.
9x=\left(-7x\right)^{2}
Calculate \sqrt{x} to the power of 2 and get x.
9x=\left(-7\right)^{2}x^{2}
Expand \left(-7x\right)^{2}.
9x=49x^{2}
Calculate -7 to the power of 2 and get 49.
9x-49x^{2}=0
Subtract 49x^{2} from both sides.
x\left(9-49x\right)=0
Factor out x.
x=0 x=\frac{9}{49}
To find equation solutions, solve x=0 and 9-49x=0.
7\times 0-3\sqrt{0}=0
Substitute 0 for x in the equation 7x-3\sqrt{x}=0.
0=0
Simplify. The value x=0 satisfies the equation.
7\times \frac{9}{49}-3\sqrt{\frac{9}{49}}=0
Substitute \frac{9}{49} for x in the equation 7x-3\sqrt{x}=0.
0=0
Simplify. The value x=\frac{9}{49} satisfies the equation.
x=0 x=\frac{9}{49}
List all solutions of -3\sqrt{x}=-7x.
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