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\left(x+2\right)\left(x+2\right)-16=\left(x-2\right)\times 3
Variable x cannot be equal to any of the values -2,2 since division by zero is not defined. Multiply both sides of the equation by \left(x-2\right)\left(x+2\right), the least common multiple of x-2,x^{2}-4,x+2.
\left(x+2\right)^{2}-16=\left(x-2\right)\times 3
Multiply x+2 and x+2 to get \left(x+2\right)^{2}.
x^{2}+4x+4-16=\left(x-2\right)\times 3
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(x+2\right)^{2}.
x^{2}+4x-12=\left(x-2\right)\times 3
Subtract 16 from 4 to get -12.
x^{2}+4x-12=3x-6
Use the distributive property to multiply x-2 by 3.
x^{2}+4x-12-3x=-6
Subtract 3x from both sides.
x^{2}+x-12=-6
Combine 4x and -3x to get x.
x^{2}+x-12+6=0
Add 6 to both sides.
x^{2}+x-6=0
Add -12 and 6 to get -6.
a+b=1 ab=-6
To solve the equation, factor x^{2}+x-6 using formula x^{2}+\left(a+b\right)x+ab=\left(x+a\right)\left(x+b\right). To find a and b, set up a system to be solved.
-1,6 -2,3
Since ab is negative, a and b have the opposite signs. Since a+b is positive, the positive number has greater absolute value than the negative. List all such integer pairs that give product -6.
-1+6=5 -2+3=1
Calculate the sum for each pair.
a=-2 b=3
The solution is the pair that gives sum 1.
\left(x-2\right)\left(x+3\right)
Rewrite factored expression \left(x+a\right)\left(x+b\right) using the obtained values.
x=2 x=-3
To find equation solutions, solve x-2=0 and x+3=0.
x=-3
Variable x cannot be equal to 2.
\left(x+2\right)\left(x+2\right)-16=\left(x-2\right)\times 3
Variable x cannot be equal to any of the values -2,2 since division by zero is not defined. Multiply both sides of the equation by \left(x-2\right)\left(x+2\right), the least common multiple of x-2,x^{2}-4,x+2.
\left(x+2\right)^{2}-16=\left(x-2\right)\times 3
Multiply x+2 and x+2 to get \left(x+2\right)^{2}.
x^{2}+4x+4-16=\left(x-2\right)\times 3
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(x+2\right)^{2}.
x^{2}+4x-12=\left(x-2\right)\times 3
Subtract 16 from 4 to get -12.
x^{2}+4x-12=3x-6
Use the distributive property to multiply x-2 by 3.
x^{2}+4x-12-3x=-6
Subtract 3x from both sides.
x^{2}+x-12=-6
Combine 4x and -3x to get x.
x^{2}+x-12+6=0
Add 6 to both sides.
x^{2}+x-6=0
Add -12 and 6 to get -6.
a+b=1 ab=1\left(-6\right)=-6
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as x^{2}+ax+bx-6. To find a and b, set up a system to be solved.
-1,6 -2,3
Since ab is negative, a and b have the opposite signs. Since a+b is positive, the positive number has greater absolute value than the negative. List all such integer pairs that give product -6.
-1+6=5 -2+3=1
Calculate the sum for each pair.
a=-2 b=3
The solution is the pair that gives sum 1.
\left(x^{2}-2x\right)+\left(3x-6\right)
Rewrite x^{2}+x-6 as \left(x^{2}-2x\right)+\left(3x-6\right).
x\left(x-2\right)+3\left(x-2\right)
Factor out x in the first and 3 in the second group.
\left(x-2\right)\left(x+3\right)
Factor out common term x-2 by using distributive property.
x=2 x=-3
To find equation solutions, solve x-2=0 and x+3=0.
x=-3
Variable x cannot be equal to 2.
\left(x+2\right)\left(x+2\right)-16=\left(x-2\right)\times 3
Variable x cannot be equal to any of the values -2,2 since division by zero is not defined. Multiply both sides of the equation by \left(x-2\right)\left(x+2\right), the least common multiple of x-2,x^{2}-4,x+2.
\left(x+2\right)^{2}-16=\left(x-2\right)\times 3
Multiply x+2 and x+2 to get \left(x+2\right)^{2}.
x^{2}+4x+4-16=\left(x-2\right)\times 3
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(x+2\right)^{2}.
x^{2}+4x-12=\left(x-2\right)\times 3
Subtract 16 from 4 to get -12.
x^{2}+4x-12=3x-6
Use the distributive property to multiply x-2 by 3.
x^{2}+4x-12-3x=-6
Subtract 3x from both sides.
x^{2}+x-12=-6
Combine 4x and -3x to get x.
x^{2}+x-12+6=0
Add 6 to both sides.
x^{2}+x-6=0
Add -12 and 6 to get -6.
x=\frac{-1±\sqrt{1^{2}-4\left(-6\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 1 for b, and -6 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-1±\sqrt{1-4\left(-6\right)}}{2}
Square 1.
x=\frac{-1±\sqrt{1+24}}{2}
Multiply -4 times -6.
x=\frac{-1±\sqrt{25}}{2}
Add 1 to 24.
x=\frac{-1±5}{2}
Take the square root of 25.
x=\frac{4}{2}
Now solve the equation x=\frac{-1±5}{2} when ± is plus. Add -1 to 5.
x=2
Divide 4 by 2.
x=-\frac{6}{2}
Now solve the equation x=\frac{-1±5}{2} when ± is minus. Subtract 5 from -1.
x=-3
Divide -6 by 2.
x=2 x=-3
The equation is now solved.
x=-3
Variable x cannot be equal to 2.
\left(x+2\right)\left(x+2\right)-16=\left(x-2\right)\times 3
Variable x cannot be equal to any of the values -2,2 since division by zero is not defined. Multiply both sides of the equation by \left(x-2\right)\left(x+2\right), the least common multiple of x-2,x^{2}-4,x+2.
\left(x+2\right)^{2}-16=\left(x-2\right)\times 3
Multiply x+2 and x+2 to get \left(x+2\right)^{2}.
x^{2}+4x+4-16=\left(x-2\right)\times 3
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(x+2\right)^{2}.
x^{2}+4x-12=\left(x-2\right)\times 3
Subtract 16 from 4 to get -12.
x^{2}+4x-12=3x-6
Use the distributive property to multiply x-2 by 3.
x^{2}+4x-12-3x=-6
Subtract 3x from both sides.
x^{2}+x-12=-6
Combine 4x and -3x to get x.
x^{2}+x=-6+12
Add 12 to both sides.
x^{2}+x=6
Add -6 and 12 to get 6.
x^{2}+x+\left(\frac{1}{2}\right)^{2}=6+\left(\frac{1}{2}\right)^{2}
Divide 1, the coefficient of the x term, by 2 to get \frac{1}{2}. Then add the square of \frac{1}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+x+\frac{1}{4}=6+\frac{1}{4}
Square \frac{1}{2} by squaring both the numerator and the denominator of the fraction.
x^{2}+x+\frac{1}{4}=\frac{25}{4}
Add 6 to \frac{1}{4}.
\left(x+\frac{1}{2}\right)^{2}=\frac{25}{4}
Factor x^{2}+x+\frac{1}{4}. 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{1}{2}\right)^{2}}=\sqrt{\frac{25}{4}}
Take the square root of both sides of the equation.
x+\frac{1}{2}=\frac{5}{2} x+\frac{1}{2}=-\frac{5}{2}
Simplify.
x=2 x=-3
Subtract \frac{1}{2} from both sides of the equation.
x=-3
Variable x cannot be equal to 2.