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\left(x+2\right)\left(x-4\right)=1
Variable x cannot be equal to any of the values -3,-2 since division by zero is not defined. Multiply both sides of the equation by \left(x+2\right)\left(x+3\right), the least common multiple of x+3,x^{2}+5x+6.
x^{2}-2x-8=1
Use the distributive property to multiply x+2 by x-4 and combine like terms.
x^{2}-2x-8-1=0
Subtract 1 from both sides.
x^{2}-2x-9=0
Subtract 1 from -8 to get -9.
x=\frac{-\left(-2\right)±\sqrt{\left(-2\right)^{2}-4\left(-9\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -2 for b, and -9 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-2\right)±\sqrt{4-4\left(-9\right)}}{2}
Square -2.
x=\frac{-\left(-2\right)±\sqrt{4+36}}{2}
Multiply -4 times -9.
x=\frac{-\left(-2\right)±\sqrt{40}}{2}
Add 4 to 36.
x=\frac{-\left(-2\right)±2\sqrt{10}}{2}
Take the square root of 40.
x=\frac{2±2\sqrt{10}}{2}
The opposite of -2 is 2.
x=\frac{2\sqrt{10}+2}{2}
Now solve the equation x=\frac{2±2\sqrt{10}}{2} when ± is plus. Add 2 to 2\sqrt{10}.
x=\sqrt{10}+1
Divide 2+2\sqrt{10} by 2.
x=\frac{2-2\sqrt{10}}{2}
Now solve the equation x=\frac{2±2\sqrt{10}}{2} when ± is minus. Subtract 2\sqrt{10} from 2.
x=1-\sqrt{10}
Divide 2-2\sqrt{10} by 2.
x=\sqrt{10}+1 x=1-\sqrt{10}
The equation is now solved.
\left(x+2\right)\left(x-4\right)=1
Variable x cannot be equal to any of the values -3,-2 since division by zero is not defined. Multiply both sides of the equation by \left(x+2\right)\left(x+3\right), the least common multiple of x+3,x^{2}+5x+6.
x^{2}-2x-8=1
Use the distributive property to multiply x+2 by x-4 and combine like terms.
x^{2}-2x=1+8
Add 8 to both sides.
x^{2}-2x=9
Add 1 and 8 to get 9.
x^{2}-2x+1=9+1
Divide -2, the coefficient of the x term, by 2 to get -1. Then add the square of -1 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-2x+1=10
Add 9 to 1.
\left(x-1\right)^{2}=10
Factor x^{2}-2x+1. 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-1\right)^{2}}=\sqrt{10}
Take the square root of both sides of the equation.
x-1=\sqrt{10} x-1=-\sqrt{10}
Simplify.
x=\sqrt{10}+1 x=1-\sqrt{10}
Add 1 to both sides of the equation.