Solve for x
x=-5
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x^{2}+8x+11+\left(x+2\right)\left(x-1\right)=\left(x+3\right)\left(x-2\right)
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^{2}+5x+6,x+3,x+2.
x^{2}+8x+11+x^{2}+x-2=\left(x+3\right)\left(x-2\right)
Use the distributive property to multiply x+2 by x-1 and combine like terms.
2x^{2}+8x+11+x-2=\left(x+3\right)\left(x-2\right)
Combine x^{2} and x^{2} to get 2x^{2}.
2x^{2}+9x+11-2=\left(x+3\right)\left(x-2\right)
Combine 8x and x to get 9x.
2x^{2}+9x+9=\left(x+3\right)\left(x-2\right)
Subtract 2 from 11 to get 9.
2x^{2}+9x+9=x^{2}+x-6
Use the distributive property to multiply x+3 by x-2 and combine like terms.
2x^{2}+9x+9-x^{2}=x-6
Subtract x^{2} from both sides.
x^{2}+9x+9=x-6
Combine 2x^{2} and -x^{2} to get x^{2}.
x^{2}+9x+9-x=-6
Subtract x from both sides.
x^{2}+8x+9=-6
Combine 9x and -x to get 8x.
x^{2}+8x+9+6=0
Add 6 to both sides.
x^{2}+8x+15=0
Add 9 and 6 to get 15.
a+b=8 ab=15
To solve the equation, factor x^{2}+8x+15 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.
1,15 3,5
Since ab is positive, a and b have the same sign. Since a+b is positive, a and b are both positive. List all such integer pairs that give product 15.
1+15=16 3+5=8
Calculate the sum for each pair.
a=3 b=5
The solution is the pair that gives sum 8.
\left(x+3\right)\left(x+5\right)
Rewrite factored expression \left(x+a\right)\left(x+b\right) using the obtained values.
x=-3 x=-5
To find equation solutions, solve x+3=0 and x+5=0.
x=-5
Variable x cannot be equal to -3.
x^{2}+8x+11+\left(x+2\right)\left(x-1\right)=\left(x+3\right)\left(x-2\right)
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^{2}+5x+6,x+3,x+2.
x^{2}+8x+11+x^{2}+x-2=\left(x+3\right)\left(x-2\right)
Use the distributive property to multiply x+2 by x-1 and combine like terms.
2x^{2}+8x+11+x-2=\left(x+3\right)\left(x-2\right)
Combine x^{2} and x^{2} to get 2x^{2}.
2x^{2}+9x+11-2=\left(x+3\right)\left(x-2\right)
Combine 8x and x to get 9x.
2x^{2}+9x+9=\left(x+3\right)\left(x-2\right)
Subtract 2 from 11 to get 9.
2x^{2}+9x+9=x^{2}+x-6
Use the distributive property to multiply x+3 by x-2 and combine like terms.
2x^{2}+9x+9-x^{2}=x-6
Subtract x^{2} from both sides.
x^{2}+9x+9=x-6
Combine 2x^{2} and -x^{2} to get x^{2}.
x^{2}+9x+9-x=-6
Subtract x from both sides.
x^{2}+8x+9=-6
Combine 9x and -x to get 8x.
x^{2}+8x+9+6=0
Add 6 to both sides.
x^{2}+8x+15=0
Add 9 and 6 to get 15.
a+b=8 ab=1\times 15=15
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as x^{2}+ax+bx+15. To find a and b, set up a system to be solved.
1,15 3,5
Since ab is positive, a and b have the same sign. Since a+b is positive, a and b are both positive. List all such integer pairs that give product 15.
1+15=16 3+5=8
Calculate the sum for each pair.
a=3 b=5
The solution is the pair that gives sum 8.
\left(x^{2}+3x\right)+\left(5x+15\right)
Rewrite x^{2}+8x+15 as \left(x^{2}+3x\right)+\left(5x+15\right).
x\left(x+3\right)+5\left(x+3\right)
Factor out x in the first and 5 in the second group.
\left(x+3\right)\left(x+5\right)
Factor out common term x+3 by using distributive property.
x=-3 x=-5
To find equation solutions, solve x+3=0 and x+5=0.
x=-5
Variable x cannot be equal to -3.
x^{2}+8x+11+\left(x+2\right)\left(x-1\right)=\left(x+3\right)\left(x-2\right)
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^{2}+5x+6,x+3,x+2.
x^{2}+8x+11+x^{2}+x-2=\left(x+3\right)\left(x-2\right)
Use the distributive property to multiply x+2 by x-1 and combine like terms.
2x^{2}+8x+11+x-2=\left(x+3\right)\left(x-2\right)
Combine x^{2} and x^{2} to get 2x^{2}.
2x^{2}+9x+11-2=\left(x+3\right)\left(x-2\right)
Combine 8x and x to get 9x.
2x^{2}+9x+9=\left(x+3\right)\left(x-2\right)
Subtract 2 from 11 to get 9.
2x^{2}+9x+9=x^{2}+x-6
Use the distributive property to multiply x+3 by x-2 and combine like terms.
2x^{2}+9x+9-x^{2}=x-6
Subtract x^{2} from both sides.
x^{2}+9x+9=x-6
Combine 2x^{2} and -x^{2} to get x^{2}.
x^{2}+9x+9-x=-6
Subtract x from both sides.
x^{2}+8x+9=-6
Combine 9x and -x to get 8x.
x^{2}+8x+9+6=0
Add 6 to both sides.
x^{2}+8x+15=0
Add 9 and 6 to get 15.
x=\frac{-8±\sqrt{8^{2}-4\times 15}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 8 for b, and 15 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-8±\sqrt{64-4\times 15}}{2}
Square 8.
x=\frac{-8±\sqrt{64-60}}{2}
Multiply -4 times 15.
x=\frac{-8±\sqrt{4}}{2}
Add 64 to -60.
x=\frac{-8±2}{2}
Take the square root of 4.
x=-\frac{6}{2}
Now solve the equation x=\frac{-8±2}{2} when ± is plus. Add -8 to 2.
x=-3
Divide -6 by 2.
x=-\frac{10}{2}
Now solve the equation x=\frac{-8±2}{2} when ± is minus. Subtract 2 from -8.
x=-5
Divide -10 by 2.
x=-3 x=-5
The equation is now solved.
x=-5
Variable x cannot be equal to -3.
x^{2}+8x+11+\left(x+2\right)\left(x-1\right)=\left(x+3\right)\left(x-2\right)
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^{2}+5x+6,x+3,x+2.
x^{2}+8x+11+x^{2}+x-2=\left(x+3\right)\left(x-2\right)
Use the distributive property to multiply x+2 by x-1 and combine like terms.
2x^{2}+8x+11+x-2=\left(x+3\right)\left(x-2\right)
Combine x^{2} and x^{2} to get 2x^{2}.
2x^{2}+9x+11-2=\left(x+3\right)\left(x-2\right)
Combine 8x and x to get 9x.
2x^{2}+9x+9=\left(x+3\right)\left(x-2\right)
Subtract 2 from 11 to get 9.
2x^{2}+9x+9=x^{2}+x-6
Use the distributive property to multiply x+3 by x-2 and combine like terms.
2x^{2}+9x+9-x^{2}=x-6
Subtract x^{2} from both sides.
x^{2}+9x+9=x-6
Combine 2x^{2} and -x^{2} to get x^{2}.
x^{2}+9x+9-x=-6
Subtract x from both sides.
x^{2}+8x+9=-6
Combine 9x and -x to get 8x.
x^{2}+8x=-6-9
Subtract 9 from both sides.
x^{2}+8x=-15
Subtract 9 from -6 to get -15.
x^{2}+8x+4^{2}=-15+4^{2}
Divide 8, the coefficient of the x term, by 2 to get 4. Then add the square of 4 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+8x+16=-15+16
Square 4.
x^{2}+8x+16=1
Add -15 to 16.
\left(x+4\right)^{2}=1
Factor x^{2}+8x+16. 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+4\right)^{2}}=\sqrt{1}
Take the square root of both sides of the equation.
x+4=1 x+4=-1
Simplify.
x=-3 x=-5
Subtract 4 from both sides of the equation.
x=-5
Variable x cannot be equal to -3.
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