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3+1=m+\frac{-m^{2}+m}{2}
Multiply both sides of the equation by 2.
4=m+\frac{-m^{2}+m}{2}
Add 3 and 1 to get 4.
m+\frac{-m^{2}+m}{2}=4
Swap sides so that all variable terms are on the left hand side.
m+\frac{-m^{2}+m}{2}-4=0
Subtract 4 from both sides.
2m-m^{2}+m-8=0
Multiply both sides of the equation by 2.
-m^{2}+m+2m-8=0
Reorder the terms.
-m^{2}+3m-8=0
Combine m and 2m to get 3m.
m=\frac{-3±\sqrt{3^{2}-4\left(-1\right)\left(-8\right)}}{2\left(-1\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -1 for a, 3 for b, and -8 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
m=\frac{-3±\sqrt{9-4\left(-1\right)\left(-8\right)}}{2\left(-1\right)}
Square 3.
m=\frac{-3±\sqrt{9+4\left(-8\right)}}{2\left(-1\right)}
Multiply -4 times -1.
m=\frac{-3±\sqrt{9-32}}{2\left(-1\right)}
Multiply 4 times -8.
m=\frac{-3±\sqrt{-23}}{2\left(-1\right)}
Add 9 to -32.
m=\frac{-3±\sqrt{23}i}{2\left(-1\right)}
Take the square root of -23.
m=\frac{-3±\sqrt{23}i}{-2}
Multiply 2 times -1.
m=\frac{-3+\sqrt{23}i}{-2}
Now solve the equation m=\frac{-3±\sqrt{23}i}{-2} when ± is plus. Add -3 to i\sqrt{23}.
m=\frac{-\sqrt{23}i+3}{2}
Divide -3+i\sqrt{23} by -2.
m=\frac{-\sqrt{23}i-3}{-2}
Now solve the equation m=\frac{-3±\sqrt{23}i}{-2} when ± is minus. Subtract i\sqrt{23} from -3.
m=\frac{3+\sqrt{23}i}{2}
Divide -3-i\sqrt{23} by -2.
m=\frac{-\sqrt{23}i+3}{2} m=\frac{3+\sqrt{23}i}{2}
The equation is now solved.
3+1=m+\frac{-m^{2}+m}{2}
Multiply both sides of the equation by 2.
4=m+\frac{-m^{2}+m}{2}
Add 3 and 1 to get 4.
m+\frac{-m^{2}+m}{2}=4
Swap sides so that all variable terms are on the left hand side.
2m-m^{2}+m=8
Multiply both sides of the equation by 2.
2m+m-m^{2}=8
Reorder the terms.
3m-m^{2}=8
Combine 2m and m to get 3m.
-m^{2}+3m=8
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{-m^{2}+3m}{-1}=\frac{8}{-1}
Divide both sides by -1.
m^{2}+\frac{3}{-1}m=\frac{8}{-1}
Dividing by -1 undoes the multiplication by -1.
m^{2}-3m=\frac{8}{-1}
Divide 3 by -1.
m^{2}-3m=-8
Divide 8 by -1.
m^{2}-3m+\left(-\frac{3}{2}\right)^{2}=-8+\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.
m^{2}-3m+\frac{9}{4}=-8+\frac{9}{4}
Square -\frac{3}{2} by squaring both the numerator and the denominator of the fraction.
m^{2}-3m+\frac{9}{4}=-\frac{23}{4}
Add -8 to \frac{9}{4}.
\left(m-\frac{3}{2}\right)^{2}=-\frac{23}{4}
Factor m^{2}-3m+\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(m-\frac{3}{2}\right)^{2}}=\sqrt{-\frac{23}{4}}
Take the square root of both sides of the equation.
m-\frac{3}{2}=\frac{\sqrt{23}i}{2} m-\frac{3}{2}=-\frac{\sqrt{23}i}{2}
Simplify.
m=\frac{3+\sqrt{23}i}{2} m=\frac{-\sqrt{23}i+3}{2}
Add \frac{3}{2} to both sides of the equation.