Solve for x
x=2
x=-2
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\left(x+1\right)\left(x+4\right)-x\times 3=2x\left(x+1\right)
Variable x cannot be equal to any of the values -1,0 since division by zero is not defined. Multiply both sides of the equation by x\left(x+1\right), the least common multiple of x,x+1.
x^{2}+5x+4-x\times 3=2x\left(x+1\right)
Use the distributive property to multiply x+1 by x+4 and combine like terms.
x^{2}+5x+4-x\times 3=2x^{2}+2x
Use the distributive property to multiply 2x by x+1.
x^{2}+5x+4-x\times 3-2x^{2}=2x
Subtract 2x^{2} from both sides.
-x^{2}+5x+4-x\times 3=2x
Combine x^{2} and -2x^{2} to get -x^{2}.
-x^{2}+5x+4-x\times 3-2x=0
Subtract 2x from both sides.
-x^{2}+3x+4-x\times 3=0
Combine 5x and -2x to get 3x.
-x^{2}+3x-x\times 3=-4
Subtract 4 from both sides. Anything subtracted from zero gives its negation.
-x^{2}+3x-3x=-4
Multiply -1 and 3 to get -3.
-x^{2}=-4
Combine 3x and -3x to get 0.
x^{2}=\frac{-4}{-1}
Divide both sides by -1.
x^{2}=4
Fraction \frac{-4}{-1} can be simplified to 4 by removing the negative sign from both the numerator and the denominator.
x=2 x=-2
Take the square root of both sides of the equation.
\left(x+1\right)\left(x+4\right)-x\times 3=2x\left(x+1\right)
Variable x cannot be equal to any of the values -1,0 since division by zero is not defined. Multiply both sides of the equation by x\left(x+1\right), the least common multiple of x,x+1.
x^{2}+5x+4-x\times 3=2x\left(x+1\right)
Use the distributive property to multiply x+1 by x+4 and combine like terms.
x^{2}+5x+4-x\times 3=2x^{2}+2x
Use the distributive property to multiply 2x by x+1.
x^{2}+5x+4-x\times 3-2x^{2}=2x
Subtract 2x^{2} from both sides.
-x^{2}+5x+4-x\times 3=2x
Combine x^{2} and -2x^{2} to get -x^{2}.
-x^{2}+5x+4-x\times 3-2x=0
Subtract 2x from both sides.
-x^{2}+3x+4-x\times 3=0
Combine 5x and -2x to get 3x.
-x^{2}+3x+4-3x=0
Multiply -1 and 3 to get -3.
-x^{2}+4=0
Combine 3x and -3x to get 0.
x=\frac{0±\sqrt{0^{2}-4\left(-1\right)\times 4}}{2\left(-1\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -1 for a, 0 for b, and 4 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\left(-1\right)\times 4}}{2\left(-1\right)}
Square 0.
x=\frac{0±\sqrt{4\times 4}}{2\left(-1\right)}
Multiply -4 times -1.
x=\frac{0±\sqrt{16}}{2\left(-1\right)}
Multiply 4 times 4.
x=\frac{0±4}{2\left(-1\right)}
Take the square root of 16.
x=\frac{0±4}{-2}
Multiply 2 times -1.
x=-2
Now solve the equation x=\frac{0±4}{-2} when ± is plus. Divide 4 by -2.
x=2
Now solve the equation x=\frac{0±4}{-2} when ± is minus. Divide -4 by -2.
x=-2 x=2
The equation is now solved.
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