Solve for m
m=-1
m=2
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m^{2}-m-6=-4
Use the distributive property to multiply m+2 by m-3 and combine like terms.
m^{2}-m-6+4=0
Add 4 to both sides.
m^{2}-m-2=0
Add -6 and 4 to get -2.
m=\frac{-\left(-1\right)±\sqrt{1-4\left(-2\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -1 for b, and -2 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
m=\frac{-\left(-1\right)±\sqrt{1+8}}{2}
Multiply -4 times -2.
m=\frac{-\left(-1\right)±\sqrt{9}}{2}
Add 1 to 8.
m=\frac{-\left(-1\right)±3}{2}
Take the square root of 9.
m=\frac{1±3}{2}
The opposite of -1 is 1.
m=\frac{4}{2}
Now solve the equation m=\frac{1±3}{2} when ± is plus. Add 1 to 3.
m=2
Divide 4 by 2.
m=-\frac{2}{2}
Now solve the equation m=\frac{1±3}{2} when ± is minus. Subtract 3 from 1.
m=-1
Divide -2 by 2.
m=2 m=-1
The equation is now solved.
m^{2}-m-6=-4
Use the distributive property to multiply m+2 by m-3 and combine like terms.
m^{2}-m=-4+6
Add 6 to both sides.
m^{2}-m=2
Add -4 and 6 to get 2.
m^{2}-m+\left(-\frac{1}{2}\right)^{2}=2+\left(-\frac{1}{2}\right)^{2}
Divide -1, the coefficient of the x term, by 2 to get -\frac{1}{2}. Then add the square of -\frac{1}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
m^{2}-m+\frac{1}{4}=2+\frac{1}{4}
Square -\frac{1}{2} by squaring both the numerator and the denominator of the fraction.
m^{2}-m+\frac{1}{4}=\frac{9}{4}
Add 2 to \frac{1}{4}.
\left(m-\frac{1}{2}\right)^{2}=\frac{9}{4}
Factor m^{2}-m+\frac{1}{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{1}{2}\right)^{2}}=\sqrt{\frac{9}{4}}
Take the square root of both sides of the equation.
m-\frac{1}{2}=\frac{3}{2} m-\frac{1}{2}=-\frac{3}{2}
Simplify.
m=2 m=-1
Add \frac{1}{2} to both sides of the equation.
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Limits
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