Solve for x
x=6
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\left(x-2\right)\left(2x-5\right)+\left(x+1\right)\times 4=\left(x+1\right)\left(x+2\right)
Variable x cannot be equal to any of the values -2,-1,2 since division by zero is not defined. Multiply both sides of the equation by \left(x-2\right)\left(x+1\right)\left(x+2\right), the least common multiple of x^{2}+3x+2,x^{2}-4,x-2.
2x^{2}-9x+10+\left(x+1\right)\times 4=\left(x+1\right)\left(x+2\right)
Use the distributive property to multiply x-2 by 2x-5 and combine like terms.
2x^{2}-9x+10+4x+4=\left(x+1\right)\left(x+2\right)
Use the distributive property to multiply x+1 by 4.
2x^{2}-5x+10+4=\left(x+1\right)\left(x+2\right)
Combine -9x and 4x to get -5x.
2x^{2}-5x+14=\left(x+1\right)\left(x+2\right)
Add 10 and 4 to get 14.
2x^{2}-5x+14=x^{2}+3x+2
Use the distributive property to multiply x+1 by x+2 and combine like terms.
2x^{2}-5x+14-x^{2}=3x+2
Subtract x^{2} from both sides.
x^{2}-5x+14=3x+2
Combine 2x^{2} and -x^{2} to get x^{2}.
x^{2}-5x+14-3x=2
Subtract 3x from both sides.
x^{2}-8x+14=2
Combine -5x and -3x to get -8x.
x^{2}-8x+14-2=0
Subtract 2 from both sides.
x^{2}-8x+12=0
Subtract 2 from 14 to get 12.
a+b=-8 ab=12
To solve the equation, factor x^{2}-8x+12 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,-12 -2,-6 -3,-4
Since ab is positive, a and b have the same sign. Since a+b is negative, a and b are both negative. List all such integer pairs that give product 12.
-1-12=-13 -2-6=-8 -3-4=-7
Calculate the sum for each pair.
a=-6 b=-2
The solution is the pair that gives sum -8.
\left(x-6\right)\left(x-2\right)
Rewrite factored expression \left(x+a\right)\left(x+b\right) using the obtained values.
x=6 x=2
To find equation solutions, solve x-6=0 and x-2=0.
x=6
Variable x cannot be equal to 2.
\left(x-2\right)\left(2x-5\right)+\left(x+1\right)\times 4=\left(x+1\right)\left(x+2\right)
Variable x cannot be equal to any of the values -2,-1,2 since division by zero is not defined. Multiply both sides of the equation by \left(x-2\right)\left(x+1\right)\left(x+2\right), the least common multiple of x^{2}+3x+2,x^{2}-4,x-2.
2x^{2}-9x+10+\left(x+1\right)\times 4=\left(x+1\right)\left(x+2\right)
Use the distributive property to multiply x-2 by 2x-5 and combine like terms.
2x^{2}-9x+10+4x+4=\left(x+1\right)\left(x+2\right)
Use the distributive property to multiply x+1 by 4.
2x^{2}-5x+10+4=\left(x+1\right)\left(x+2\right)
Combine -9x and 4x to get -5x.
2x^{2}-5x+14=\left(x+1\right)\left(x+2\right)
Add 10 and 4 to get 14.
2x^{2}-5x+14=x^{2}+3x+2
Use the distributive property to multiply x+1 by x+2 and combine like terms.
2x^{2}-5x+14-x^{2}=3x+2
Subtract x^{2} from both sides.
x^{2}-5x+14=3x+2
Combine 2x^{2} and -x^{2} to get x^{2}.
x^{2}-5x+14-3x=2
Subtract 3x from both sides.
x^{2}-8x+14=2
Combine -5x and -3x to get -8x.
x^{2}-8x+14-2=0
Subtract 2 from both sides.
x^{2}-8x+12=0
Subtract 2 from 14 to get 12.
a+b=-8 ab=1\times 12=12
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as x^{2}+ax+bx+12. To find a and b, set up a system to be solved.
-1,-12 -2,-6 -3,-4
Since ab is positive, a and b have the same sign. Since a+b is negative, a and b are both negative. List all such integer pairs that give product 12.
-1-12=-13 -2-6=-8 -3-4=-7
Calculate the sum for each pair.
a=-6 b=-2
The solution is the pair that gives sum -8.
\left(x^{2}-6x\right)+\left(-2x+12\right)
Rewrite x^{2}-8x+12 as \left(x^{2}-6x\right)+\left(-2x+12\right).
x\left(x-6\right)-2\left(x-6\right)
Factor out x in the first and -2 in the second group.
\left(x-6\right)\left(x-2\right)
Factor out common term x-6 by using distributive property.
x=6 x=2
To find equation solutions, solve x-6=0 and x-2=0.
x=6
Variable x cannot be equal to 2.
\left(x-2\right)\left(2x-5\right)+\left(x+1\right)\times 4=\left(x+1\right)\left(x+2\right)
Variable x cannot be equal to any of the values -2,-1,2 since division by zero is not defined. Multiply both sides of the equation by \left(x-2\right)\left(x+1\right)\left(x+2\right), the least common multiple of x^{2}+3x+2,x^{2}-4,x-2.
2x^{2}-9x+10+\left(x+1\right)\times 4=\left(x+1\right)\left(x+2\right)
Use the distributive property to multiply x-2 by 2x-5 and combine like terms.
2x^{2}-9x+10+4x+4=\left(x+1\right)\left(x+2\right)
Use the distributive property to multiply x+1 by 4.
2x^{2}-5x+10+4=\left(x+1\right)\left(x+2\right)
Combine -9x and 4x to get -5x.
2x^{2}-5x+14=\left(x+1\right)\left(x+2\right)
Add 10 and 4 to get 14.
2x^{2}-5x+14=x^{2}+3x+2
Use the distributive property to multiply x+1 by x+2 and combine like terms.
2x^{2}-5x+14-x^{2}=3x+2
Subtract x^{2} from both sides.
x^{2}-5x+14=3x+2
Combine 2x^{2} and -x^{2} to get x^{2}.
x^{2}-5x+14-3x=2
Subtract 3x from both sides.
x^{2}-8x+14=2
Combine -5x and -3x to get -8x.
x^{2}-8x+14-2=0
Subtract 2 from both sides.
x^{2}-8x+12=0
Subtract 2 from 14 to get 12.
x=\frac{-\left(-8\right)±\sqrt{\left(-8\right)^{2}-4\times 12}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -8 for b, and 12 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-8\right)±\sqrt{64-4\times 12}}{2}
Square -8.
x=\frac{-\left(-8\right)±\sqrt{64-48}}{2}
Multiply -4 times 12.
x=\frac{-\left(-8\right)±\sqrt{16}}{2}
Add 64 to -48.
x=\frac{-\left(-8\right)±4}{2}
Take the square root of 16.
x=\frac{8±4}{2}
The opposite of -8 is 8.
x=\frac{12}{2}
Now solve the equation x=\frac{8±4}{2} when ± is plus. Add 8 to 4.
x=6
Divide 12 by 2.
x=\frac{4}{2}
Now solve the equation x=\frac{8±4}{2} when ± is minus. Subtract 4 from 8.
x=2
Divide 4 by 2.
x=6 x=2
The equation is now solved.
x=6
Variable x cannot be equal to 2.
\left(x-2\right)\left(2x-5\right)+\left(x+1\right)\times 4=\left(x+1\right)\left(x+2\right)
Variable x cannot be equal to any of the values -2,-1,2 since division by zero is not defined. Multiply both sides of the equation by \left(x-2\right)\left(x+1\right)\left(x+2\right), the least common multiple of x^{2}+3x+2,x^{2}-4,x-2.
2x^{2}-9x+10+\left(x+1\right)\times 4=\left(x+1\right)\left(x+2\right)
Use the distributive property to multiply x-2 by 2x-5 and combine like terms.
2x^{2}-9x+10+4x+4=\left(x+1\right)\left(x+2\right)
Use the distributive property to multiply x+1 by 4.
2x^{2}-5x+10+4=\left(x+1\right)\left(x+2\right)
Combine -9x and 4x to get -5x.
2x^{2}-5x+14=\left(x+1\right)\left(x+2\right)
Add 10 and 4 to get 14.
2x^{2}-5x+14=x^{2}+3x+2
Use the distributive property to multiply x+1 by x+2 and combine like terms.
2x^{2}-5x+14-x^{2}=3x+2
Subtract x^{2} from both sides.
x^{2}-5x+14=3x+2
Combine 2x^{2} and -x^{2} to get x^{2}.
x^{2}-5x+14-3x=2
Subtract 3x from both sides.
x^{2}-8x+14=2
Combine -5x and -3x to get -8x.
x^{2}-8x=2-14
Subtract 14 from both sides.
x^{2}-8x=-12
Subtract 14 from 2 to get -12.
x^{2}-8x+\left(-4\right)^{2}=-12+\left(-4\right)^{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=-12+16
Square -4.
x^{2}-8x+16=4
Add -12 to 16.
\left(x-4\right)^{2}=4
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{4}
Take the square root of both sides of the equation.
x-4=2 x-4=-2
Simplify.
x=6 x=2
Add 4 to both sides of the equation.
x=6
Variable x cannot be equal to 2.
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