Solve for x
x=-1
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x+2-x\left(2x+1\right)=0
Variable x cannot be equal to any of the values -2,0,1 since division by zero is not defined. Multiply both sides of the equation by x\left(x-1\right)\left(x+2\right), the least common multiple of x^{2}-x,x^{2}+x-2.
x+2-\left(2x^{2}+x\right)=0
Use the distributive property to multiply x by 2x+1.
x+2-2x^{2}-x=0
To find the opposite of 2x^{2}+x, find the opposite of each term.
2-2x^{2}=0
Combine x and -x to get 0.
-2x^{2}=-2
Subtract 2 from both sides. Anything subtracted from zero gives its negation.
x^{2}=\frac{-2}{-2}
Divide both sides by -2.
x^{2}=1
Divide -2 by -2 to get 1.
x=1 x=-1
Take the square root of both sides of the equation.
x=-1
Variable x cannot be equal to 1.
x+2-x\left(2x+1\right)=0
Variable x cannot be equal to any of the values -2,0,1 since division by zero is not defined. Multiply both sides of the equation by x\left(x-1\right)\left(x+2\right), the least common multiple of x^{2}-x,x^{2}+x-2.
x+2-\left(2x^{2}+x\right)=0
Use the distributive property to multiply x by 2x+1.
x+2-2x^{2}-x=0
To find the opposite of 2x^{2}+x, find the opposite of each term.
2-2x^{2}=0
Combine x and -x to get 0.
-2x^{2}+2=0
Quadratic equations like this one, with an x^{2} term but no x term, can still be solved using the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}, once they are put in standard form: ax^{2}+bx+c=0.
x=\frac{0±\sqrt{0^{2}-4\left(-2\right)\times 2}}{2\left(-2\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -2 for a, 0 for b, and 2 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\left(-2\right)\times 2}}{2\left(-2\right)}
Square 0.
x=\frac{0±\sqrt{8\times 2}}{2\left(-2\right)}
Multiply -4 times -2.
x=\frac{0±\sqrt{16}}{2\left(-2\right)}
Multiply 8 times 2.
x=\frac{0±4}{2\left(-2\right)}
Take the square root of 16.
x=\frac{0±4}{-4}
Multiply 2 times -2.
x=-1
Now solve the equation x=\frac{0±4}{-4} when ± is plus. Divide 4 by -4.
x=1
Now solve the equation x=\frac{0±4}{-4} when ± is minus. Divide -4 by -4.
x=-1 x=1
The equation is now solved.
x=-1
Variable x cannot be equal to 1.
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