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-15x^{2}+9x=0
Use the distributive property to multiply -3x by 5x-3.
x\left(-15x+9\right)=0
Factor out x.
x=0 x=\frac{3}{5}
To find equation solutions, solve x=0 and -15x+9=0.
-15x^{2}+9x=0
Use the distributive property to multiply -3x by 5x-3.
x=\frac{-9±\sqrt{9^{2}}}{2\left(-15\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -15 for a, 9 for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-9±9}{2\left(-15\right)}
Take the square root of 9^{2}.
x=\frac{-9±9}{-30}
Multiply 2 times -15.
x=\frac{0}{-30}
Now solve the equation x=\frac{-9±9}{-30} when ± is plus. Add -9 to 9.
x=0
Divide 0 by -30.
x=-\frac{18}{-30}
Now solve the equation x=\frac{-9±9}{-30} when ± is minus. Subtract 9 from -9.
x=\frac{3}{5}
Reduce the fraction \frac{-18}{-30} to lowest terms by extracting and canceling out 6.
x=0 x=\frac{3}{5}
The equation is now solved.
-15x^{2}+9x=0
Use the distributive property to multiply -3x by 5x-3.
\frac{-15x^{2}+9x}{-15}=\frac{0}{-15}
Divide both sides by -15.
x^{2}+\frac{9}{-15}x=\frac{0}{-15}
Dividing by -15 undoes the multiplication by -15.
x^{2}-\frac{3}{5}x=\frac{0}{-15}
Reduce the fraction \frac{9}{-15} to lowest terms by extracting and canceling out 3.
x^{2}-\frac{3}{5}x=0
Divide 0 by -15.
x^{2}-\frac{3}{5}x+\left(-\frac{3}{10}\right)^{2}=\left(-\frac{3}{10}\right)^{2}
Divide -\frac{3}{5}, the coefficient of the x term, by 2 to get -\frac{3}{10}. Then add the square of -\frac{3}{10} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{3}{5}x+\frac{9}{100}=\frac{9}{100}
Square -\frac{3}{10} by squaring both the numerator and the denominator of the fraction.
\left(x-\frac{3}{10}\right)^{2}=\frac{9}{100}
Factor x^{2}-\frac{3}{5}x+\frac{9}{100}. In general, when x^{2}+bx+c is a perfect square, it can always be factored as \left(x+\frac{b}{2}\right)^{2}.
\sqrt{\left(x-\frac{3}{10}\right)^{2}}=\sqrt{\frac{9}{100}}
Take the square root of both sides of the equation.
x-\frac{3}{10}=\frac{3}{10} x-\frac{3}{10}=-\frac{3}{10}
Simplify.
x=\frac{3}{5} x=0
Add \frac{3}{10} to both sides of the equation.