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\left(x-2\right)\left(x+2\right)\times 2+\left(x-2\right)\times 4=6x-4
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.
\left(x^{2}-4\right)\times 2+\left(x-2\right)\times 4=6x-4
Consider \left(x-2\right)\left(x+2\right). Multiplication can be transformed into difference of squares using the rule: \left(a-b\right)\left(a+b\right)=a^{2}-b^{2}. Square 2.
2x^{2}-8+\left(x-2\right)\times 4=6x-4
Use the distributive property to multiply x^{2}-4 by 2.
2x^{2}-8+4x-8=6x-4
Use the distributive property to multiply x-2 by 4.
2x^{2}-16+4x=6x-4
Subtract 8 from -8 to get -16.
2x^{2}-16+4x-6x=-4
Subtract 6x from both sides.
2x^{2}-16-2x=-4
Combine 4x and -6x to get -2x.
2x^{2}-16-2x+4=0
Add 4 to both sides.
2x^{2}-12-2x=0
Add -16 and 4 to get -12.
x^{2}-6-x=0
Divide both sides by 2.
x^{2}-x-6=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
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 negative, the negative number has greater absolute value than the positive. List all such integer pairs that give product -6.
1-6=-5 2-3=-1
Calculate the sum for each pair.
a=-3 b=2
The solution is the pair that gives sum -1.
\left(x^{2}-3x\right)+\left(2x-6\right)
Rewrite x^{2}-x-6 as \left(x^{2}-3x\right)+\left(2x-6\right).
x\left(x-3\right)+2\left(x-3\right)
Factor out x in the first and 2 in the second group.
\left(x-3\right)\left(x+2\right)
Factor out common term x-3 by using distributive property.
x=3 x=-2
To find equation solutions, solve x-3=0 and x+2=0.
x=3
Variable x cannot be equal to -2.
\left(x-2\right)\left(x+2\right)\times 2+\left(x-2\right)\times 4=6x-4
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.
\left(x^{2}-4\right)\times 2+\left(x-2\right)\times 4=6x-4
Consider \left(x-2\right)\left(x+2\right). Multiplication can be transformed into difference of squares using the rule: \left(a-b\right)\left(a+b\right)=a^{2}-b^{2}. Square 2.
2x^{2}-8+\left(x-2\right)\times 4=6x-4
Use the distributive property to multiply x^{2}-4 by 2.
2x^{2}-8+4x-8=6x-4
Use the distributive property to multiply x-2 by 4.
2x^{2}-16+4x=6x-4
Subtract 8 from -8 to get -16.
2x^{2}-16+4x-6x=-4
Subtract 6x from both sides.
2x^{2}-16-2x=-4
Combine 4x and -6x to get -2x.
2x^{2}-16-2x+4=0
Add 4 to both sides.
2x^{2}-12-2x=0
Add -16 and 4 to get -12.
2x^{2}-2x-12=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(-2\right)±\sqrt{\left(-2\right)^{2}-4\times 2\left(-12\right)}}{2\times 2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 2 for a, -2 for b, and -12 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-2\right)±\sqrt{4-4\times 2\left(-12\right)}}{2\times 2}
Square -2.
x=\frac{-\left(-2\right)±\sqrt{4-8\left(-12\right)}}{2\times 2}
Multiply -4 times 2.
x=\frac{-\left(-2\right)±\sqrt{4+96}}{2\times 2}
Multiply -8 times -12.
x=\frac{-\left(-2\right)±\sqrt{100}}{2\times 2}
Add 4 to 96.
x=\frac{-\left(-2\right)±10}{2\times 2}
Take the square root of 100.
x=\frac{2±10}{2\times 2}
The opposite of -2 is 2.
x=\frac{2±10}{4}
Multiply 2 times 2.
x=\frac{12}{4}
Now solve the equation x=\frac{2±10}{4} when ± is plus. Add 2 to 10.
x=3
Divide 12 by 4.
x=-\frac{8}{4}
Now solve the equation x=\frac{2±10}{4} when ± is minus. Subtract 10 from 2.
x=-2
Divide -8 by 4.
x=3 x=-2
The equation is now solved.
x=3
Variable x cannot be equal to -2.
\left(x-2\right)\left(x+2\right)\times 2+\left(x-2\right)\times 4=6x-4
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.
\left(x^{2}-4\right)\times 2+\left(x-2\right)\times 4=6x-4
Consider \left(x-2\right)\left(x+2\right). Multiplication can be transformed into difference of squares using the rule: \left(a-b\right)\left(a+b\right)=a^{2}-b^{2}. Square 2.
2x^{2}-8+\left(x-2\right)\times 4=6x-4
Use the distributive property to multiply x^{2}-4 by 2.
2x^{2}-8+4x-8=6x-4
Use the distributive property to multiply x-2 by 4.
2x^{2}-16+4x=6x-4
Subtract 8 from -8 to get -16.
2x^{2}-16+4x-6x=-4
Subtract 6x from both sides.
2x^{2}-16-2x=-4
Combine 4x and -6x to get -2x.
2x^{2}-2x=-4+16
Add 16 to both sides.
2x^{2}-2x=12
Add -4 and 16 to get 12.
\frac{2x^{2}-2x}{2}=\frac{12}{2}
Divide both sides by 2.
x^{2}+\left(-\frac{2}{2}\right)x=\frac{12}{2}
Dividing by 2 undoes the multiplication by 2.
x^{2}-x=\frac{12}{2}
Divide -2 by 2.
x^{2}-x=6
Divide 12 by 2.
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=3 x=-2
Add \frac{1}{2} to both sides of the equation.
x=3
Variable x cannot be equal to -2.