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-12x^{2}+28x-15=-15
Use the distributive property to multiply -6x+5 by 2x-3 and combine like terms.
-12x^{2}+28x-15+15=0
Add 15 to both sides.
-12x^{2}+28x=0
Add -15 and 15 to get 0.
x=\frac{-28±\sqrt{28^{2}}}{2\left(-12\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -12 for a, 28 for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-28±28}{2\left(-12\right)}
Take the square root of 28^{2}.
x=\frac{-28±28}{-24}
Multiply 2 times -12.
x=\frac{0}{-24}
Now solve the equation x=\frac{-28±28}{-24} when ± is plus. Add -28 to 28.
x=0
Divide 0 by -24.
x=-\frac{56}{-24}
Now solve the equation x=\frac{-28±28}{-24} when ± is minus. Subtract 28 from -28.
x=\frac{7}{3}
Reduce the fraction \frac{-56}{-24} to lowest terms by extracting and canceling out 8.
x=0 x=\frac{7}{3}
The equation is now solved.
-12x^{2}+28x-15=-15
Use the distributive property to multiply -6x+5 by 2x-3 and combine like terms.
-12x^{2}+28x=-15+15
Add 15 to both sides.
-12x^{2}+28x=0
Add -15 and 15 to get 0.
\frac{-12x^{2}+28x}{-12}=\frac{0}{-12}
Divide both sides by -12.
x^{2}+\frac{28}{-12}x=\frac{0}{-12}
Dividing by -12 undoes the multiplication by -12.
x^{2}-\frac{7}{3}x=\frac{0}{-12}
Reduce the fraction \frac{28}{-12} to lowest terms by extracting and canceling out 4.
x^{2}-\frac{7}{3}x=0
Divide 0 by -12.
x^{2}-\frac{7}{3}x+\left(-\frac{7}{6}\right)^{2}=\left(-\frac{7}{6}\right)^{2}
Divide -\frac{7}{3}, the coefficient of the x term, by 2 to get -\frac{7}{6}. Then add the square of -\frac{7}{6} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{7}{3}x+\frac{49}{36}=\frac{49}{36}
Square -\frac{7}{6} by squaring both the numerator and the denominator of the fraction.
\left(x-\frac{7}{6}\right)^{2}=\frac{49}{36}
Factor x^{2}-\frac{7}{3}x+\frac{49}{36}. 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{7}{6}\right)^{2}}=\sqrt{\frac{49}{36}}
Take the square root of both sides of the equation.
x-\frac{7}{6}=\frac{7}{6} x-\frac{7}{6}=-\frac{7}{6}
Simplify.
x=\frac{7}{3} x=0
Add \frac{7}{6} to both sides of the equation.