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x^{2}-6x+9=9\left(3+x\right)^{2}
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-3\right)^{2}.
x^{2}-6x+9=9\left(9+6x+x^{2}\right)
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(3+x\right)^{2}.
x^{2}-6x+9=81+54x+9x^{2}
Use the distributive property to multiply 9 by 9+6x+x^{2}.
x^{2}-6x+9-81=54x+9x^{2}
Subtract 81 from both sides.
x^{2}-6x-72=54x+9x^{2}
Subtract 81 from 9 to get -72.
x^{2}-6x-72-54x=9x^{2}
Subtract 54x from both sides.
x^{2}-60x-72=9x^{2}
Combine -6x and -54x to get -60x.
x^{2}-60x-72-9x^{2}=0
Subtract 9x^{2} from both sides.
-8x^{2}-60x-72=0
Combine x^{2} and -9x^{2} to get -8x^{2}.
-2x^{2}-15x-18=0
Divide both sides by 4.
a+b=-15 ab=-2\left(-18\right)=36
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as -2x^{2}+ax+bx-18. To find a and b, set up a system to be solved.
-1,-36 -2,-18 -3,-12 -4,-9 -6,-6
Since ab is positive, a and b have the same sign. Since a+b is negative, a and b are both negative. List all such integer pairs that give product 36.
-1-36=-37 -2-18=-20 -3-12=-15 -4-9=-13 -6-6=-12
Calculate the sum for each pair.
a=-3 b=-12
The solution is the pair that gives sum -15.
\left(-2x^{2}-3x\right)+\left(-12x-18\right)
Rewrite -2x^{2}-15x-18 as \left(-2x^{2}-3x\right)+\left(-12x-18\right).
-x\left(2x+3\right)-6\left(2x+3\right)
Factor out -x in the first and -6 in the second group.
\left(2x+3\right)\left(-x-6\right)
Factor out common term 2x+3 by using distributive property.
x=-\frac{3}{2} x=-6
To find equation solutions, solve 2x+3=0 and -x-6=0.
x^{2}-6x+9=9\left(3+x\right)^{2}
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-3\right)^{2}.
x^{2}-6x+9=9\left(9+6x+x^{2}\right)
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(3+x\right)^{2}.
x^{2}-6x+9=81+54x+9x^{2}
Use the distributive property to multiply 9 by 9+6x+x^{2}.
x^{2}-6x+9-81=54x+9x^{2}
Subtract 81 from both sides.
x^{2}-6x-72=54x+9x^{2}
Subtract 81 from 9 to get -72.
x^{2}-6x-72-54x=9x^{2}
Subtract 54x from both sides.
x^{2}-60x-72=9x^{2}
Combine -6x and -54x to get -60x.
x^{2}-60x-72-9x^{2}=0
Subtract 9x^{2} from both sides.
-8x^{2}-60x-72=0
Combine x^{2} and -9x^{2} to get -8x^{2}.
x=\frac{-\left(-60\right)±\sqrt{\left(-60\right)^{2}-4\left(-8\right)\left(-72\right)}}{2\left(-8\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -8 for a, -60 for b, and -72 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-60\right)±\sqrt{3600-4\left(-8\right)\left(-72\right)}}{2\left(-8\right)}
Square -60.
x=\frac{-\left(-60\right)±\sqrt{3600+32\left(-72\right)}}{2\left(-8\right)}
Multiply -4 times -8.
x=\frac{-\left(-60\right)±\sqrt{3600-2304}}{2\left(-8\right)}
Multiply 32 times -72.
x=\frac{-\left(-60\right)±\sqrt{1296}}{2\left(-8\right)}
Add 3600 to -2304.
x=\frac{-\left(-60\right)±36}{2\left(-8\right)}
Take the square root of 1296.
x=\frac{60±36}{2\left(-8\right)}
The opposite of -60 is 60.
x=\frac{60±36}{-16}
Multiply 2 times -8.
x=\frac{96}{-16}
Now solve the equation x=\frac{60±36}{-16} when ± is plus. Add 60 to 36.
x=-6
Divide 96 by -16.
x=\frac{24}{-16}
Now solve the equation x=\frac{60±36}{-16} when ± is minus. Subtract 36 from 60.
x=-\frac{3}{2}
Reduce the fraction \frac{24}{-16} to lowest terms by extracting and canceling out 8.
x=-6 x=-\frac{3}{2}
The equation is now solved.
x^{2}-6x+9=9\left(3+x\right)^{2}
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-3\right)^{2}.
x^{2}-6x+9=9\left(9+6x+x^{2}\right)
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(3+x\right)^{2}.
x^{2}-6x+9=81+54x+9x^{2}
Use the distributive property to multiply 9 by 9+6x+x^{2}.
x^{2}-6x+9-54x=81+9x^{2}
Subtract 54x from both sides.
x^{2}-60x+9=81+9x^{2}
Combine -6x and -54x to get -60x.
x^{2}-60x+9-9x^{2}=81
Subtract 9x^{2} from both sides.
-8x^{2}-60x+9=81
Combine x^{2} and -9x^{2} to get -8x^{2}.
-8x^{2}-60x=81-9
Subtract 9 from both sides.
-8x^{2}-60x=72
Subtract 9 from 81 to get 72.
\frac{-8x^{2}-60x}{-8}=\frac{72}{-8}
Divide both sides by -8.
x^{2}+\left(-\frac{60}{-8}\right)x=\frac{72}{-8}
Dividing by -8 undoes the multiplication by -8.
x^{2}+\frac{15}{2}x=\frac{72}{-8}
Reduce the fraction \frac{-60}{-8} to lowest terms by extracting and canceling out 4.
x^{2}+\frac{15}{2}x=-9
Divide 72 by -8.
x^{2}+\frac{15}{2}x+\left(\frac{15}{4}\right)^{2}=-9+\left(\frac{15}{4}\right)^{2}
Divide \frac{15}{2}, the coefficient of the x term, by 2 to get \frac{15}{4}. Then add the square of \frac{15}{4} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+\frac{15}{2}x+\frac{225}{16}=-9+\frac{225}{16}
Square \frac{15}{4} by squaring both the numerator and the denominator of the fraction.
x^{2}+\frac{15}{2}x+\frac{225}{16}=\frac{81}{16}
Add -9 to \frac{225}{16}.
\left(x+\frac{15}{4}\right)^{2}=\frac{81}{16}
Factor x^{2}+\frac{15}{2}x+\frac{225}{16}. 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{15}{4}\right)^{2}}=\sqrt{\frac{81}{16}}
Take the square root of both sides of the equation.
x+\frac{15}{4}=\frac{9}{4} x+\frac{15}{4}=-\frac{9}{4}
Simplify.
x=-\frac{3}{2} x=-6
Subtract \frac{15}{4} from both sides of the equation.