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x^{2}+5x+\left(x+1\right)\left(x+1\right)=10\left(x+1\right)
Variable x cannot be equal to -1 since division by zero is not defined. Multiply both sides of the equation by x+1.
x^{2}+5x+\left(x+1\right)^{2}=10\left(x+1\right)
Multiply x+1 and x+1 to get \left(x+1\right)^{2}.
x^{2}+5x+x^{2}+2x+1=10\left(x+1\right)
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(x+1\right)^{2}.
2x^{2}+5x+2x+1=10\left(x+1\right)
Combine x^{2} and x^{2} to get 2x^{2}.
2x^{2}+7x+1=10\left(x+1\right)
Combine 5x and 2x to get 7x.
2x^{2}+7x+1=10x+10
Use the distributive property to multiply 10 by x+1.
2x^{2}+7x+1-10x=10
Subtract 10x from both sides.
2x^{2}-3x+1=10
Combine 7x and -10x to get -3x.
2x^{2}-3x+1-10=0
Subtract 10 from both sides.
2x^{2}-3x-9=0
Subtract 10 from 1 to get -9.
a+b=-3 ab=2\left(-9\right)=-18
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as 2x^{2}+ax+bx-9. To find a and b, set up a system to be solved.
1,-18 2,-9 3,-6
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 -18.
1-18=-17 2-9=-7 3-6=-3
Calculate the sum for each pair.
a=-6 b=3
The solution is the pair that gives sum -3.
\left(2x^{2}-6x\right)+\left(3x-9\right)
Rewrite 2x^{2}-3x-9 as \left(2x^{2}-6x\right)+\left(3x-9\right).
2x\left(x-3\right)+3\left(x-3\right)
Factor out 2x in the first and 3 in the second group.
\left(x-3\right)\left(2x+3\right)
Factor out common term x-3 by using distributive property.
x=3 x=-\frac{3}{2}
To find equation solutions, solve x-3=0 and 2x+3=0.
x^{2}+5x+\left(x+1\right)\left(x+1\right)=10\left(x+1\right)
Variable x cannot be equal to -1 since division by zero is not defined. Multiply both sides of the equation by x+1.
x^{2}+5x+\left(x+1\right)^{2}=10\left(x+1\right)
Multiply x+1 and x+1 to get \left(x+1\right)^{2}.
x^{2}+5x+x^{2}+2x+1=10\left(x+1\right)
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(x+1\right)^{2}.
2x^{2}+5x+2x+1=10\left(x+1\right)
Combine x^{2} and x^{2} to get 2x^{2}.
2x^{2}+7x+1=10\left(x+1\right)
Combine 5x and 2x to get 7x.
2x^{2}+7x+1=10x+10
Use the distributive property to multiply 10 by x+1.
2x^{2}+7x+1-10x=10
Subtract 10x from both sides.
2x^{2}-3x+1=10
Combine 7x and -10x to get -3x.
2x^{2}-3x+1-10=0
Subtract 10 from both sides.
2x^{2}-3x-9=0
Subtract 10 from 1 to get -9.
x=\frac{-\left(-3\right)±\sqrt{\left(-3\right)^{2}-4\times 2\left(-9\right)}}{2\times 2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 2 for a, -3 for b, and -9 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-3\right)±\sqrt{9-4\times 2\left(-9\right)}}{2\times 2}
Square -3.
x=\frac{-\left(-3\right)±\sqrt{9-8\left(-9\right)}}{2\times 2}
Multiply -4 times 2.
x=\frac{-\left(-3\right)±\sqrt{9+72}}{2\times 2}
Multiply -8 times -9.
x=\frac{-\left(-3\right)±\sqrt{81}}{2\times 2}
Add 9 to 72.
x=\frac{-\left(-3\right)±9}{2\times 2}
Take the square root of 81.
x=\frac{3±9}{2\times 2}
The opposite of -3 is 3.
x=\frac{3±9}{4}
Multiply 2 times 2.
x=\frac{12}{4}
Now solve the equation x=\frac{3±9}{4} when ± is plus. Add 3 to 9.
x=3
Divide 12 by 4.
x=-\frac{6}{4}
Now solve the equation x=\frac{3±9}{4} when ± is minus. Subtract 9 from 3.
x=-\frac{3}{2}
Reduce the fraction \frac{-6}{4} to lowest terms by extracting and canceling out 2.
x=3 x=-\frac{3}{2}
The equation is now solved.
x^{2}+5x+\left(x+1\right)\left(x+1\right)=10\left(x+1\right)
Variable x cannot be equal to -1 since division by zero is not defined. Multiply both sides of the equation by x+1.
x^{2}+5x+\left(x+1\right)^{2}=10\left(x+1\right)
Multiply x+1 and x+1 to get \left(x+1\right)^{2}.
x^{2}+5x+x^{2}+2x+1=10\left(x+1\right)
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(x+1\right)^{2}.
2x^{2}+5x+2x+1=10\left(x+1\right)
Combine x^{2} and x^{2} to get 2x^{2}.
2x^{2}+7x+1=10\left(x+1\right)
Combine 5x and 2x to get 7x.
2x^{2}+7x+1=10x+10
Use the distributive property to multiply 10 by x+1.
2x^{2}+7x+1-10x=10
Subtract 10x from both sides.
2x^{2}-3x+1=10
Combine 7x and -10x to get -3x.
2x^{2}-3x=10-1
Subtract 1 from both sides.
2x^{2}-3x=9
Subtract 1 from 10 to get 9.
\frac{2x^{2}-3x}{2}=\frac{9}{2}
Divide both sides by 2.
x^{2}-\frac{3}{2}x=\frac{9}{2}
Dividing by 2 undoes the multiplication by 2.
x^{2}-\frac{3}{2}x+\left(-\frac{3}{4}\right)^{2}=\frac{9}{2}+\left(-\frac{3}{4}\right)^{2}
Divide -\frac{3}{2}, the coefficient of the x term, by 2 to get -\frac{3}{4}. Then add the square of -\frac{3}{4} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{3}{2}x+\frac{9}{16}=\frac{9}{2}+\frac{9}{16}
Square -\frac{3}{4} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{3}{2}x+\frac{9}{16}=\frac{81}{16}
Add \frac{9}{2} to \frac{9}{16} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x-\frac{3}{4}\right)^{2}=\frac{81}{16}
Factor x^{2}-\frac{3}{2}x+\frac{9}{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-\frac{3}{4}\right)^{2}}=\sqrt{\frac{81}{16}}
Take the square root of both sides of the equation.
x-\frac{3}{4}=\frac{9}{4} x-\frac{3}{4}=-\frac{9}{4}
Simplify.
x=3 x=-\frac{3}{2}
Add \frac{3}{4} to both sides of the equation.