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3\left(x-3\right)\times 2+\left(x-3\right)\left(x+4\right)=\left(x-3\right)\left(4x+4\right)+3\left(2-x\right)
Variable x cannot be equal to 3 since division by zero is not defined. Multiply both sides of the equation by 3\left(x-3\right), the least common multiple of 3,x-3.
\left(3x-9\right)\times 2+\left(x-3\right)\left(x+4\right)=\left(x-3\right)\left(4x+4\right)+3\left(2-x\right)
Use the distributive property to multiply 3 by x-3.
6x-18+\left(x-3\right)\left(x+4\right)=\left(x-3\right)\left(4x+4\right)+3\left(2-x\right)
Use the distributive property to multiply 3x-9 by 2.
6x-18+x^{2}+x-12=\left(x-3\right)\left(4x+4\right)+3\left(2-x\right)
Use the distributive property to multiply x-3 by x+4 and combine like terms.
7x-18+x^{2}-12=\left(x-3\right)\left(4x+4\right)+3\left(2-x\right)
Combine 6x and x to get 7x.
7x-30+x^{2}=\left(x-3\right)\left(4x+4\right)+3\left(2-x\right)
Subtract 12 from -18 to get -30.
7x-30+x^{2}=4x^{2}-8x-12+3\left(2-x\right)
Use the distributive property to multiply x-3 by 4x+4 and combine like terms.
7x-30+x^{2}=4x^{2}-8x-12+6-3x
Use the distributive property to multiply 3 by 2-x.
7x-30+x^{2}=4x^{2}-8x-6-3x
Add -12 and 6 to get -6.
7x-30+x^{2}=4x^{2}-11x-6
Combine -8x and -3x to get -11x.
7x-30+x^{2}-4x^{2}=-11x-6
Subtract 4x^{2} from both sides.
7x-30-3x^{2}=-11x-6
Combine x^{2} and -4x^{2} to get -3x^{2}.
7x-30-3x^{2}+11x=-6
Add 11x to both sides.
18x-30-3x^{2}=-6
Combine 7x and 11x to get 18x.
18x-30-3x^{2}+6=0
Add 6 to both sides.
18x-24-3x^{2}=0
Add -30 and 6 to get -24.
-3x^{2}+18x-24=0
All equations of the form ax^{2}+bx+c=0 can be solved using the quadratic formula: \frac{-b±\sqrt{b^{2}-4ac}}{2a}. The quadratic formula gives two solutions, one when ± is addition and one when it is subtraction.
x=\frac{-18±\sqrt{18^{2}-4\left(-3\right)\left(-24\right)}}{2\left(-3\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -3 for a, 18 for b, and -24 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-18±\sqrt{324-4\left(-3\right)\left(-24\right)}}{2\left(-3\right)}
Square 18.
x=\frac{-18±\sqrt{324+12\left(-24\right)}}{2\left(-3\right)}
Multiply -4 times -3.
x=\frac{-18±\sqrt{324-288}}{2\left(-3\right)}
Multiply 12 times -24.
x=\frac{-18±\sqrt{36}}{2\left(-3\right)}
Add 324 to -288.
x=\frac{-18±6}{2\left(-3\right)}
Take the square root of 36.
x=\frac{-18±6}{-6}
Multiply 2 times -3.
x=-\frac{12}{-6}
Now solve the equation x=\frac{-18±6}{-6} when ± is plus. Add -18 to 6.
x=2
Divide -12 by -6.
x=-\frac{24}{-6}
Now solve the equation x=\frac{-18±6}{-6} when ± is minus. Subtract 6 from -18.
x=4
Divide -24 by -6.
x=2 x=4
The equation is now solved.
3\left(x-3\right)\times 2+\left(x-3\right)\left(x+4\right)=\left(x-3\right)\left(4x+4\right)+3\left(2-x\right)
Variable x cannot be equal to 3 since division by zero is not defined. Multiply both sides of the equation by 3\left(x-3\right), the least common multiple of 3,x-3.
\left(3x-9\right)\times 2+\left(x-3\right)\left(x+4\right)=\left(x-3\right)\left(4x+4\right)+3\left(2-x\right)
Use the distributive property to multiply 3 by x-3.
6x-18+\left(x-3\right)\left(x+4\right)=\left(x-3\right)\left(4x+4\right)+3\left(2-x\right)
Use the distributive property to multiply 3x-9 by 2.
6x-18+x^{2}+x-12=\left(x-3\right)\left(4x+4\right)+3\left(2-x\right)
Use the distributive property to multiply x-3 by x+4 and combine like terms.
7x-18+x^{2}-12=\left(x-3\right)\left(4x+4\right)+3\left(2-x\right)
Combine 6x and x to get 7x.
7x-30+x^{2}=\left(x-3\right)\left(4x+4\right)+3\left(2-x\right)
Subtract 12 from -18 to get -30.
7x-30+x^{2}=4x^{2}-8x-12+3\left(2-x\right)
Use the distributive property to multiply x-3 by 4x+4 and combine like terms.
7x-30+x^{2}=4x^{2}-8x-12+6-3x
Use the distributive property to multiply 3 by 2-x.
7x-30+x^{2}=4x^{2}-8x-6-3x
Add -12 and 6 to get -6.
7x-30+x^{2}=4x^{2}-11x-6
Combine -8x and -3x to get -11x.
7x-30+x^{2}-4x^{2}=-11x-6
Subtract 4x^{2} from both sides.
7x-30-3x^{2}=-11x-6
Combine x^{2} and -4x^{2} to get -3x^{2}.
7x-30-3x^{2}+11x=-6
Add 11x to both sides.
18x-30-3x^{2}=-6
Combine 7x and 11x to get 18x.
18x-3x^{2}=-6+30
Add 30 to both sides.
18x-3x^{2}=24
Add -6 and 30 to get 24.
-3x^{2}+18x=24
Quadratic equations such as this one can be solved by completing the square. In order to complete the square, the equation must first be in the form x^{2}+bx=c.
\frac{-3x^{2}+18x}{-3}=\frac{24}{-3}
Divide both sides by -3.
x^{2}+\frac{18}{-3}x=\frac{24}{-3}
Dividing by -3 undoes the multiplication by -3.
x^{2}-6x=\frac{24}{-3}
Divide 18 by -3.
x^{2}-6x=-8
Divide 24 by -3.
x^{2}-6x+\left(-3\right)^{2}=-8+\left(-3\right)^{2}
Divide -6, the coefficient of the x term, by 2 to get -3. Then add the square of -3 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-6x+9=-8+9
Square -3.
x^{2}-6x+9=1
Add -8 to 9.
\left(x-3\right)^{2}=1
Factor x^{2}-6x+9. 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-3\right)^{2}}=\sqrt{1}
Take the square root of both sides of the equation.
x-3=1 x-3=-1
Simplify.
x=4 x=2
Add 3 to both sides of the equation.