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-3a^{2}+\left(3a-9\right)\times 3=\left(a+3\right)\times 3a
Variable a cannot be equal to any of the values -3,3 since division by zero is not defined. Multiply both sides of the equation by 3\left(a-3\right)\left(a+3\right), the least common multiple of a^{2}-9,a+3,3a-9.
-3a^{2}+9a-27=\left(a+3\right)\times 3a
Use the distributive property to multiply 3a-9 by 3.
-3a^{2}+9a-27=\left(3a+9\right)a
Use the distributive property to multiply a+3 by 3.
-3a^{2}+9a-27=3a^{2}+9a
Use the distributive property to multiply 3a+9 by a.
-3a^{2}+9a-27-3a^{2}=9a
Subtract 3a^{2} from both sides.
-6a^{2}+9a-27=9a
Combine -3a^{2} and -3a^{2} to get -6a^{2}.
-6a^{2}+9a-27-9a=0
Subtract 9a from both sides.
-6a^{2}-27=0
Combine 9a and -9a to get 0.
-6a^{2}=27
Add 27 to both sides. Anything plus zero gives itself.
a^{2}=\frac{27}{-6}
Divide both sides by -6.
a^{2}=-\frac{9}{2}
Reduce the fraction \frac{27}{-6} to lowest terms by extracting and canceling out 3.
a=\frac{3\sqrt{2}i}{2} a=-\frac{3\sqrt{2}i}{2}
The equation is now solved.
-3a^{2}+\left(3a-9\right)\times 3=\left(a+3\right)\times 3a
Variable a cannot be equal to any of the values -3,3 since division by zero is not defined. Multiply both sides of the equation by 3\left(a-3\right)\left(a+3\right), the least common multiple of a^{2}-9,a+3,3a-9.
-3a^{2}+9a-27=\left(a+3\right)\times 3a
Use the distributive property to multiply 3a-9 by 3.
-3a^{2}+9a-27=\left(3a+9\right)a
Use the distributive property to multiply a+3 by 3.
-3a^{2}+9a-27=3a^{2}+9a
Use the distributive property to multiply 3a+9 by a.
-3a^{2}+9a-27-3a^{2}=9a
Subtract 3a^{2} from both sides.
-6a^{2}+9a-27=9a
Combine -3a^{2} and -3a^{2} to get -6a^{2}.
-6a^{2}+9a-27-9a=0
Subtract 9a from both sides.
-6a^{2}-27=0
Combine 9a and -9a to get 0.
a=\frac{0±\sqrt{0^{2}-4\left(-6\right)\left(-27\right)}}{2\left(-6\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -6 for a, 0 for b, and -27 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
a=\frac{0±\sqrt{-4\left(-6\right)\left(-27\right)}}{2\left(-6\right)}
Square 0.
a=\frac{0±\sqrt{24\left(-27\right)}}{2\left(-6\right)}
Multiply -4 times -6.
a=\frac{0±\sqrt{-648}}{2\left(-6\right)}
Multiply 24 times -27.
a=\frac{0±18\sqrt{2}i}{2\left(-6\right)}
Take the square root of -648.
a=\frac{0±18\sqrt{2}i}{-12}
Multiply 2 times -6.
a=-\frac{3\sqrt{2}i}{2}
Now solve the equation a=\frac{0±18\sqrt{2}i}{-12} when ± is plus.
a=\frac{3\sqrt{2}i}{2}
Now solve the equation a=\frac{0±18\sqrt{2}i}{-12} when ± is minus.
a=-\frac{3\sqrt{2}i}{2} a=\frac{3\sqrt{2}i}{2}
The equation is now solved.