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\left(m+4\right)\left(-m\right)=3
Variable m cannot be equal to -4 since division by zero is not defined. Multiply both sides of the equation by m+4.
m\left(-m\right)+4\left(-m\right)=3
Use the distributive property to multiply m+4 by -m.
m\left(-m\right)+4\left(-m\right)-3=0
Subtract 3 from both sides.
m^{2}\left(-1\right)+4\left(-1\right)m-3=0
Multiply m and m to get m^{2}.
m^{2}\left(-1\right)-4m-3=0
Multiply 4 and -1 to get -4.
-m^{2}-4m-3=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.
m=\frac{-\left(-4\right)±\sqrt{\left(-4\right)^{2}-4\left(-1\right)\left(-3\right)}}{2\left(-1\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -1 for a, -4 for b, and -3 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
m=\frac{-\left(-4\right)±\sqrt{16-4\left(-1\right)\left(-3\right)}}{2\left(-1\right)}
Square -4.
m=\frac{-\left(-4\right)±\sqrt{16+4\left(-3\right)}}{2\left(-1\right)}
Multiply -4 times -1.
m=\frac{-\left(-4\right)±\sqrt{16-12}}{2\left(-1\right)}
Multiply 4 times -3.
m=\frac{-\left(-4\right)±\sqrt{4}}{2\left(-1\right)}
Add 16 to -12.
m=\frac{-\left(-4\right)±2}{2\left(-1\right)}
Take the square root of 4.
m=\frac{4±2}{2\left(-1\right)}
The opposite of -4 is 4.
m=\frac{4±2}{-2}
Multiply 2 times -1.
m=\frac{6}{-2}
Now solve the equation m=\frac{4±2}{-2} when ± is plus. Add 4 to 2.
m=-3
Divide 6 by -2.
m=\frac{2}{-2}
Now solve the equation m=\frac{4±2}{-2} when ± is minus. Subtract 2 from 4.
m=-1
Divide 2 by -2.
m=-3 m=-1
The equation is now solved.
\left(m+4\right)\left(-m\right)=3
Variable m cannot be equal to -4 since division by zero is not defined. Multiply both sides of the equation by m+4.
m\left(-m\right)+4\left(-m\right)=3
Use the distributive property to multiply m+4 by -m.
m^{2}\left(-1\right)+4\left(-1\right)m=3
Multiply m and m to get m^{2}.
m^{2}\left(-1\right)-4m=3
Multiply 4 and -1 to get -4.
-m^{2}-4m=3
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}-4m}{-1}=\frac{3}{-1}
Divide both sides by -1.
m^{2}+\left(-\frac{4}{-1}\right)m=\frac{3}{-1}
Dividing by -1 undoes the multiplication by -1.
m^{2}+4m=\frac{3}{-1}
Divide -4 by -1.
m^{2}+4m=-3
Divide 3 by -1.
m^{2}+4m+2^{2}=-3+2^{2}
Divide 4, the coefficient of the x term, by 2 to get 2. Then add the square of 2 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
m^{2}+4m+4=-3+4
Square 2.
m^{2}+4m+4=1
Add -3 to 4.
\left(m+2\right)^{2}=1
Factor m^{2}+4m+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+2\right)^{2}}=\sqrt{1}
Take the square root of both sides of the equation.
m+2=1 m+2=-1
Simplify.
m=-1 m=-3
Subtract 2 from both sides of the equation.