Solve for x
x=-1
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\left(x+2\right)x+\left(x-3\right)\left(2x+1\right)=\left(x+2\right)\times 3
Variable x cannot be equal to any of the values -2,3 since division by zero is not defined. Multiply both sides of the equation by \left(x-3\right)\left(x+2\right), the least common multiple of x-3,x+2.
x^{2}+2x+\left(x-3\right)\left(2x+1\right)=\left(x+2\right)\times 3
Use the distributive property to multiply x+2 by x.
x^{2}+2x+2x^{2}-5x-3=\left(x+2\right)\times 3
Use the distributive property to multiply x-3 by 2x+1 and combine like terms.
3x^{2}+2x-5x-3=\left(x+2\right)\times 3
Combine x^{2} and 2x^{2} to get 3x^{2}.
3x^{2}-3x-3=\left(x+2\right)\times 3
Combine 2x and -5x to get -3x.
3x^{2}-3x-3=3x+6
Use the distributive property to multiply x+2 by 3.
3x^{2}-3x-3-3x=6
Subtract 3x from both sides.
3x^{2}-6x-3=6
Combine -3x and -3x to get -6x.
3x^{2}-6x-3-6=0
Subtract 6 from both sides.
3x^{2}-6x-9=0
Subtract 6 from -3 to get -9.
x=\frac{-\left(-6\right)±\sqrt{\left(-6\right)^{2}-4\times 3\left(-9\right)}}{2\times 3}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 3 for a, -6 for b, and -9 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-6\right)±\sqrt{36-4\times 3\left(-9\right)}}{2\times 3}
Square -6.
x=\frac{-\left(-6\right)±\sqrt{36-12\left(-9\right)}}{2\times 3}
Multiply -4 times 3.
x=\frac{-\left(-6\right)±\sqrt{36+108}}{2\times 3}
Multiply -12 times -9.
x=\frac{-\left(-6\right)±\sqrt{144}}{2\times 3}
Add 36 to 108.
x=\frac{-\left(-6\right)±12}{2\times 3}
Take the square root of 144.
x=\frac{6±12}{2\times 3}
The opposite of -6 is 6.
x=\frac{6±12}{6}
Multiply 2 times 3.
x=\frac{18}{6}
Now solve the equation x=\frac{6±12}{6} when ± is plus. Add 6 to 12.
x=3
Divide 18 by 6.
x=-\frac{6}{6}
Now solve the equation x=\frac{6±12}{6} when ± is minus. Subtract 12 from 6.
x=-1
Divide -6 by 6.
x=3 x=-1
The equation is now solved.
x=-1
Variable x cannot be equal to 3.
\left(x+2\right)x+\left(x-3\right)\left(2x+1\right)=\left(x+2\right)\times 3
Variable x cannot be equal to any of the values -2,3 since division by zero is not defined. Multiply both sides of the equation by \left(x-3\right)\left(x+2\right), the least common multiple of x-3,x+2.
x^{2}+2x+\left(x-3\right)\left(2x+1\right)=\left(x+2\right)\times 3
Use the distributive property to multiply x+2 by x.
x^{2}+2x+2x^{2}-5x-3=\left(x+2\right)\times 3
Use the distributive property to multiply x-3 by 2x+1 and combine like terms.
3x^{2}+2x-5x-3=\left(x+2\right)\times 3
Combine x^{2} and 2x^{2} to get 3x^{2}.
3x^{2}-3x-3=\left(x+2\right)\times 3
Combine 2x and -5x to get -3x.
3x^{2}-3x-3=3x+6
Use the distributive property to multiply x+2 by 3.
3x^{2}-3x-3-3x=6
Subtract 3x from both sides.
3x^{2}-6x-3=6
Combine -3x and -3x to get -6x.
3x^{2}-6x=6+3
Add 3 to both sides.
3x^{2}-6x=9
Add 6 and 3 to get 9.
\frac{3x^{2}-6x}{3}=\frac{9}{3}
Divide both sides by 3.
x^{2}+\left(-\frac{6}{3}\right)x=\frac{9}{3}
Dividing by 3 undoes the multiplication by 3.
x^{2}-2x=\frac{9}{3}
Divide -6 by 3.
x^{2}-2x=3
Divide 9 by 3.
x^{2}-2x+1=3+1
Divide -2, the coefficient of the x term, by 2 to get -1. Then add the square of -1 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-2x+1=4
Add 3 to 1.
\left(x-1\right)^{2}=4
Factor x^{2}-2x+1. 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-1\right)^{2}}=\sqrt{4}
Take the square root of both sides of the equation.
x-1=2 x-1=-2
Simplify.
x=3 x=-1
Add 1 to both sides of the equation.
x=-1
Variable x cannot be equal to 3.
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