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3=\left(2x+3\right)x+\left(2x+3\right)\times 2
Variable x cannot be equal to -\frac{3}{2} since division by zero is not defined. Multiply both sides of the equation by 2x+3.
3=2x^{2}+3x+\left(2x+3\right)\times 2
Use the distributive property to multiply 2x+3 by x.
3=2x^{2}+3x+4x+6
Use the distributive property to multiply 2x+3 by 2.
3=2x^{2}+7x+6
Combine 3x and 4x to get 7x.
2x^{2}+7x+6=3
Swap sides so that all variable terms are on the left hand side.
2x^{2}+7x+6-3=0
Subtract 3 from both sides.
2x^{2}+7x+3=0
Subtract 3 from 6 to get 3.
x=\frac{-7±\sqrt{7^{2}-4\times 2\times 3}}{2\times 2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 2 for a, 7 for b, and 3 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-7±\sqrt{49-4\times 2\times 3}}{2\times 2}
Square 7.
x=\frac{-7±\sqrt{49-8\times 3}}{2\times 2}
Multiply -4 times 2.
x=\frac{-7±\sqrt{49-24}}{2\times 2}
Multiply -8 times 3.
x=\frac{-7±\sqrt{25}}{2\times 2}
Add 49 to -24.
x=\frac{-7±5}{2\times 2}
Take the square root of 25.
x=\frac{-7±5}{4}
Multiply 2 times 2.
x=-\frac{2}{4}
Now solve the equation x=\frac{-7±5}{4} when ± is plus. Add -7 to 5.
x=-\frac{1}{2}
Reduce the fraction \frac{-2}{4} to lowest terms by extracting and canceling out 2.
x=-\frac{12}{4}
Now solve the equation x=\frac{-7±5}{4} when ± is minus. Subtract 5 from -7.
x=-3
Divide -12 by 4.
x=-\frac{1}{2} x=-3
The equation is now solved.
3=\left(2x+3\right)x+\left(2x+3\right)\times 2
Variable x cannot be equal to -\frac{3}{2} since division by zero is not defined. Multiply both sides of the equation by 2x+3.
3=2x^{2}+3x+\left(2x+3\right)\times 2
Use the distributive property to multiply 2x+3 by x.
3=2x^{2}+3x+4x+6
Use the distributive property to multiply 2x+3 by 2.
3=2x^{2}+7x+6
Combine 3x and 4x to get 7x.
2x^{2}+7x+6=3
Swap sides so that all variable terms are on the left hand side.
2x^{2}+7x=3-6
Subtract 6 from both sides.
2x^{2}+7x=-3
Subtract 6 from 3 to get -3.
\frac{2x^{2}+7x}{2}=-\frac{3}{2}
Divide both sides by 2.
x^{2}+\frac{7}{2}x=-\frac{3}{2}
Dividing by 2 undoes the multiplication by 2.
x^{2}+\frac{7}{2}x+\left(\frac{7}{4}\right)^{2}=-\frac{3}{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}=-\frac{3}{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{25}{16}
Add -\frac{3}{2} to \frac{49}{16} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x+\frac{7}{4}\right)^{2}=\frac{25}{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{25}{16}}
Take the square root of both sides of the equation.
x+\frac{7}{4}=\frac{5}{4} x+\frac{7}{4}=-\frac{5}{4}
Simplify.
x=-\frac{1}{2} x=-3
Subtract \frac{7}{4} from both sides of the equation.