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2x^{2}+7x+3-x=3
Subtract x from both sides.
2x^{2}+6x+3=3
Combine 7x and -x to get 6x.
2x^{2}+6x+3-3=0
Subtract 3 from both sides.
2x^{2}+6x=0
Subtract 3 from 3 to get 0.
x\left(2x+6\right)=0
Factor out x.
x=0 x=-3
To find equation solutions, solve x=0 and 2x+6=0.
2x^{2}+7x+3-x=3
Subtract x from both sides.
2x^{2}+6x+3=3
Combine 7x and -x to get 6x.
2x^{2}+6x+3-3=0
Subtract 3 from both sides.
2x^{2}+6x=0
Subtract 3 from 3 to get 0.
x=\frac{-6±\sqrt{6^{2}}}{2\times 2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 2 for a, 6 for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-6±6}{2\times 2}
Take the square root of 6^{2}.
x=\frac{-6±6}{4}
Multiply 2 times 2.
x=\frac{0}{4}
Now solve the equation x=\frac{-6±6}{4} when ± is plus. Add -6 to 6.
x=0
Divide 0 by 4.
x=-\frac{12}{4}
Now solve the equation x=\frac{-6±6}{4} when ± is minus. Subtract 6 from -6.
x=-3
Divide -12 by 4.
x=0 x=-3
The equation is now solved.
2x^{2}+7x+3-x=3
Subtract x from both sides.
2x^{2}+6x+3=3
Combine 7x and -x to get 6x.
2x^{2}+6x=3-3
Subtract 3 from both sides.
2x^{2}+6x=0
Subtract 3 from 3 to get 0.
\frac{2x^{2}+6x}{2}=\frac{0}{2}
Divide both sides by 2.
x^{2}+\frac{6}{2}x=\frac{0}{2}
Dividing by 2 undoes the multiplication by 2.
x^{2}+3x=\frac{0}{2}
Divide 6 by 2.
x^{2}+3x=0
Divide 0 by 2.
x^{2}+3x+\left(\frac{3}{2}\right)^{2}=\left(\frac{3}{2}\right)^{2}
Divide 3, the coefficient of the x term, by 2 to get \frac{3}{2}. Then add the square of \frac{3}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+3x+\frac{9}{4}=\frac{9}{4}
Square \frac{3}{2} by squaring both the numerator and the denominator of the fraction.
\left(x+\frac{3}{2}\right)^{2}=\frac{9}{4}
Factor x^{2}+3x+\frac{9}{4}. 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{3}{2}\right)^{2}}=\sqrt{\frac{9}{4}}
Take the square root of both sides of the equation.
x+\frac{3}{2}=\frac{3}{2} x+\frac{3}{2}=-\frac{3}{2}
Simplify.
x=0 x=-3
Subtract \frac{3}{2} from both sides of the equation.