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2x-1=-2x\left(x+3\right)+x+3
Variable x cannot be equal to -3 since division by zero is not defined. Multiply both sides of the equation by x+3.
2x-1=-2x^{2}-6x+x+3
Use the distributive property to multiply -2x by x+3.
2x-1=-2x^{2}-5x+3
Combine -6x and x to get -5x.
2x-1+2x^{2}=-5x+3
Add 2x^{2} to both sides.
2x-1+2x^{2}+5x=3
Add 5x to both sides.
7x-1+2x^{2}=3
Combine 2x and 5x to get 7x.
7x-1+2x^{2}-3=0
Subtract 3 from both sides.
7x-4+2x^{2}=0
Subtract 3 from -1 to get -4.
2x^{2}+7x-4=0
All equations of the form ax^{2}+bx+c=0 can be solved using the quadratic formula: \frac{-b±\sqrt{b^{2}-4ac}}{2a}. The quadratic formula gives two solutions, one when ± is addition and one when it is subtraction.
x=\frac{-7±\sqrt{7^{2}-4\times 2\left(-4\right)}}{2\times 2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 2 for a, 7 for b, and -4 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-7±\sqrt{49-4\times 2\left(-4\right)}}{2\times 2}
Square 7.
x=\frac{-7±\sqrt{49-8\left(-4\right)}}{2\times 2}
Multiply -4 times 2.
x=\frac{-7±\sqrt{49+32}}{2\times 2}
Multiply -8 times -4.
x=\frac{-7±\sqrt{81}}{2\times 2}
Add 49 to 32.
x=\frac{-7±9}{2\times 2}
Take the square root of 81.
x=\frac{-7±9}{4}
Multiply 2 times 2.
x=\frac{2}{4}
Now solve the equation x=\frac{-7±9}{4} when ± is plus. Add -7 to 9.
x=\frac{1}{2}
Reduce the fraction \frac{2}{4} to lowest terms by extracting and canceling out 2.
x=-\frac{16}{4}
Now solve the equation x=\frac{-7±9}{4} when ± is minus. Subtract 9 from -7.
x=-4
Divide -16 by 4.
x=\frac{1}{2} x=-4
The equation is now solved.
2x-1=-2x\left(x+3\right)+x+3
Variable x cannot be equal to -3 since division by zero is not defined. Multiply both sides of the equation by x+3.
2x-1=-2x^{2}-6x+x+3
Use the distributive property to multiply -2x by x+3.
2x-1=-2x^{2}-5x+3
Combine -6x and x to get -5x.
2x-1+2x^{2}=-5x+3
Add 2x^{2} to both sides.
2x-1+2x^{2}+5x=3
Add 5x to both sides.
7x-1+2x^{2}=3
Combine 2x and 5x to get 7x.
7x+2x^{2}=3+1
Add 1 to both sides.
7x+2x^{2}=4
Add 3 and 1 to get 4.
2x^{2}+7x=4
Quadratic equations such as this one can be solved by completing the square. In order to complete the square, the equation must first be in the form x^{2}+bx=c.
\frac{2x^{2}+7x}{2}=\frac{4}{2}
Divide both sides by 2.
x^{2}+\frac{7}{2}x=\frac{4}{2}
Dividing by 2 undoes the multiplication by 2.
x^{2}+\frac{7}{2}x=2
Divide 4 by 2.
x^{2}+\frac{7}{2}x+\left(\frac{7}{4}\right)^{2}=2+\left(\frac{7}{4}\right)^{2}
Divide \frac{7}{2}, the coefficient of the x term, by 2 to get \frac{7}{4}. Then add the square of \frac{7}{4} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+\frac{7}{2}x+\frac{49}{16}=2+\frac{49}{16}
Square \frac{7}{4} by squaring both the numerator and the denominator of the fraction.
x^{2}+\frac{7}{2}x+\frac{49}{16}=\frac{81}{16}
Add 2 to \frac{49}{16}.
\left(x+\frac{7}{4}\right)^{2}=\frac{81}{16}
Factor x^{2}+\frac{7}{2}x+\frac{49}{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{7}{4}\right)^{2}}=\sqrt{\frac{81}{16}}
Take the square root of both sides of the equation.
x+\frac{7}{4}=\frac{9}{4} x+\frac{7}{4}=-\frac{9}{4}
Simplify.
x=\frac{1}{2} x=-4
Subtract \frac{7}{4} from both sides of the equation.