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x+5=\left(x+1\right)\left(x+5\right)
Variable x cannot be equal to any of the values -5,-1 since division by zero is not defined. Multiply both sides of the equation by \left(x+1\right)\left(x+5\right).
x+5=x^{2}+6x+5
Use the distributive property to multiply x+1 by x+5 and combine like terms.
x+5-x^{2}=6x+5
Subtract x^{2} from both sides.
x+5-x^{2}-6x=5
Subtract 6x from both sides.
-5x+5-x^{2}=5
Combine x and -6x to get -5x.
-5x+5-x^{2}-5=0
Subtract 5 from both sides.
-5x-x^{2}=0
Subtract 5 from 5 to get 0.
x\left(-5-x\right)=0
Factor out x.
x=0 x=-5
To find equation solutions, solve x=0 and -5-x=0.
x=0
Variable x cannot be equal to -5.
x+5=\left(x+1\right)\left(x+5\right)
Variable x cannot be equal to any of the values -5,-1 since division by zero is not defined. Multiply both sides of the equation by \left(x+1\right)\left(x+5\right).
x+5=x^{2}+6x+5
Use the distributive property to multiply x+1 by x+5 and combine like terms.
x+5-x^{2}=6x+5
Subtract x^{2} from both sides.
x+5-x^{2}-6x=5
Subtract 6x from both sides.
-5x+5-x^{2}=5
Combine x and -6x to get -5x.
-5x+5-x^{2}-5=0
Subtract 5 from both sides.
-5x-x^{2}=0
Subtract 5 from 5 to get 0.
-x^{2}-5x=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(-5\right)±\sqrt{\left(-5\right)^{2}}}{2\left(-1\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -1 for a, -5 for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-5\right)±5}{2\left(-1\right)}
Take the square root of \left(-5\right)^{2}.
x=\frac{5±5}{2\left(-1\right)}
The opposite of -5 is 5.
x=\frac{5±5}{-2}
Multiply 2 times -1.
x=\frac{10}{-2}
Now solve the equation x=\frac{5±5}{-2} when ± is plus. Add 5 to 5.
x=-5
Divide 10 by -2.
x=\frac{0}{-2}
Now solve the equation x=\frac{5±5}{-2} when ± is minus. Subtract 5 from 5.
x=0
Divide 0 by -2.
x=-5 x=0
The equation is now solved.
x=0
Variable x cannot be equal to -5.
x+5=\left(x+1\right)\left(x+5\right)
Variable x cannot be equal to any of the values -5,-1 since division by zero is not defined. Multiply both sides of the equation by \left(x+1\right)\left(x+5\right).
x+5=x^{2}+6x+5
Use the distributive property to multiply x+1 by x+5 and combine like terms.
x+5-x^{2}=6x+5
Subtract x^{2} from both sides.
x+5-x^{2}-6x=5
Subtract 6x from both sides.
-5x+5-x^{2}=5
Combine x and -6x to get -5x.
-5x-x^{2}=5-5
Subtract 5 from both sides.
-5x-x^{2}=0
Subtract 5 from 5 to get 0.
-x^{2}-5x=0
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{-x^{2}-5x}{-1}=\frac{0}{-1}
Divide both sides by -1.
x^{2}+\left(-\frac{5}{-1}\right)x=\frac{0}{-1}
Dividing by -1 undoes the multiplication by -1.
x^{2}+5x=\frac{0}{-1}
Divide -5 by -1.
x^{2}+5x=0
Divide 0 by -1.
x^{2}+5x+\left(\frac{5}{2}\right)^{2}=\left(\frac{5}{2}\right)^{2}
Divide 5, the coefficient of the x term, by 2 to get \frac{5}{2}. Then add the square of \frac{5}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+5x+\frac{25}{4}=\frac{25}{4}
Square \frac{5}{2} by squaring both the numerator and the denominator of the fraction.
\left(x+\frac{5}{2}\right)^{2}=\frac{25}{4}
Factor x^{2}+5x+\frac{25}{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{5}{2}\right)^{2}}=\sqrt{\frac{25}{4}}
Take the square root of both sides of the equation.
x+\frac{5}{2}=\frac{5}{2} x+\frac{5}{2}=-\frac{5}{2}
Simplify.
x=0 x=-5
Subtract \frac{5}{2} from both sides of the equation.
x=0
Variable x cannot be equal to -5.