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x=-3\left(x^{2}-4x+4\right)+4
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-2\right)^{2}.
x=-3x^{2}+12x-12+4
Use the distributive property to multiply -3 by x^{2}-4x+4.
x=-3x^{2}+12x-8
Add -12 and 4 to get -8.
x+3x^{2}=12x-8
Add 3x^{2} to both sides.
x+3x^{2}-12x=-8
Subtract 12x from both sides.
-11x+3x^{2}=-8
Combine x and -12x to get -11x.
-11x+3x^{2}+8=0
Add 8 to both sides.
3x^{2}-11x+8=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=-11 ab=3\times 8=24
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as 3x^{2}+ax+bx+8. To find a and b, set up a system to be solved.
-1,-24 -2,-12 -3,-8 -4,-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 24.
-1-24=-25 -2-12=-14 -3-8=-11 -4-6=-10
Calculate the sum for each pair.
a=-8 b=-3
The solution is the pair that gives sum -11.
\left(3x^{2}-8x\right)+\left(-3x+8\right)
Rewrite 3x^{2}-11x+8 as \left(3x^{2}-8x\right)+\left(-3x+8\right).
x\left(3x-8\right)-\left(3x-8\right)
Factor out x in the first and -1 in the second group.
\left(3x-8\right)\left(x-1\right)
Factor out common term 3x-8 by using distributive property.
x=\frac{8}{3} x=1
To find equation solutions, solve 3x-8=0 and x-1=0.
x=-3\left(x^{2}-4x+4\right)+4
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-2\right)^{2}.
x=-3x^{2}+12x-12+4
Use the distributive property to multiply -3 by x^{2}-4x+4.
x=-3x^{2}+12x-8
Add -12 and 4 to get -8.
x+3x^{2}=12x-8
Add 3x^{2} to both sides.
x+3x^{2}-12x=-8
Subtract 12x from both sides.
-11x+3x^{2}=-8
Combine x and -12x to get -11x.
-11x+3x^{2}+8=0
Add 8 to both sides.
3x^{2}-11x+8=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{-\left(-11\right)±\sqrt{\left(-11\right)^{2}-4\times 3\times 8}}{2\times 3}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 3 for a, -11 for b, and 8 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-11\right)±\sqrt{121-4\times 3\times 8}}{2\times 3}
Square -11.
x=\frac{-\left(-11\right)±\sqrt{121-12\times 8}}{2\times 3}
Multiply -4 times 3.
x=\frac{-\left(-11\right)±\sqrt{121-96}}{2\times 3}
Multiply -12 times 8.
x=\frac{-\left(-11\right)±\sqrt{25}}{2\times 3}
Add 121 to -96.
x=\frac{-\left(-11\right)±5}{2\times 3}
Take the square root of 25.
x=\frac{11±5}{2\times 3}
The opposite of -11 is 11.
x=\frac{11±5}{6}
Multiply 2 times 3.
x=\frac{16}{6}
Now solve the equation x=\frac{11±5}{6} when ± is plus. Add 11 to 5.
x=\frac{8}{3}
Reduce the fraction \frac{16}{6} to lowest terms by extracting and canceling out 2.
x=\frac{6}{6}
Now solve the equation x=\frac{11±5}{6} when ± is minus. Subtract 5 from 11.
x=1
Divide 6 by 6.
x=\frac{8}{3} x=1
The equation is now solved.
x=-3\left(x^{2}-4x+4\right)+4
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-2\right)^{2}.
x=-3x^{2}+12x-12+4
Use the distributive property to multiply -3 by x^{2}-4x+4.
x=-3x^{2}+12x-8
Add -12 and 4 to get -8.
x+3x^{2}=12x-8
Add 3x^{2} to both sides.
x+3x^{2}-12x=-8
Subtract 12x from both sides.
-11x+3x^{2}=-8
Combine x and -12x to get -11x.
3x^{2}-11x=-8
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}-11x}{3}=-\frac{8}{3}
Divide both sides by 3.
x^{2}-\frac{11}{3}x=-\frac{8}{3}
Dividing by 3 undoes the multiplication by 3.
x^{2}-\frac{11}{3}x+\left(-\frac{11}{6}\right)^{2}=-\frac{8}{3}+\left(-\frac{11}{6}\right)^{2}
Divide -\frac{11}{3}, the coefficient of the x term, by 2 to get -\frac{11}{6}. Then add the square of -\frac{11}{6} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{11}{3}x+\frac{121}{36}=-\frac{8}{3}+\frac{121}{36}
Square -\frac{11}{6} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{11}{3}x+\frac{121}{36}=\frac{25}{36}
Add -\frac{8}{3} to \frac{121}{36} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x-\frac{11}{6}\right)^{2}=\frac{25}{36}
Factor x^{2}-\frac{11}{3}x+\frac{121}{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{11}{6}\right)^{2}}=\sqrt{\frac{25}{36}}
Take the square root of both sides of the equation.
x-\frac{11}{6}=\frac{5}{6} x-\frac{11}{6}=-\frac{5}{6}
Simplify.
x=\frac{8}{3} x=1
Add \frac{11}{6} to both sides of the equation.