Solve for m
m=-6
m=5
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\left(m-2\right)\left(m+3\right)=3\times 8
Variable m cannot be equal to 2 since division by zero is not defined. Multiply both sides of the equation by 3\left(m-2\right), the least common multiple of 3,m-2.
m^{2}+m-6=3\times 8
Use the distributive property to multiply m-2 by m+3 and combine like terms.
m^{2}+m-6=24
Multiply 3 and 8 to get 24.
m^{2}+m-6-24=0
Subtract 24 from both sides.
m^{2}+m-30=0
Subtract 24 from -6 to get -30.
m=\frac{-1±\sqrt{1^{2}-4\left(-30\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 1 for b, and -30 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
m=\frac{-1±\sqrt{1-4\left(-30\right)}}{2}
Square 1.
m=\frac{-1±\sqrt{1+120}}{2}
Multiply -4 times -30.
m=\frac{-1±\sqrt{121}}{2}
Add 1 to 120.
m=\frac{-1±11}{2}
Take the square root of 121.
m=\frac{10}{2}
Now solve the equation m=\frac{-1±11}{2} when ± is plus. Add -1 to 11.
m=5
Divide 10 by 2.
m=-\frac{12}{2}
Now solve the equation m=\frac{-1±11}{2} when ± is minus. Subtract 11 from -1.
m=-6
Divide -12 by 2.
m=5 m=-6
The equation is now solved.
\left(m-2\right)\left(m+3\right)=3\times 8
Variable m cannot be equal to 2 since division by zero is not defined. Multiply both sides of the equation by 3\left(m-2\right), the least common multiple of 3,m-2.
m^{2}+m-6=3\times 8
Use the distributive property to multiply m-2 by m+3 and combine like terms.
m^{2}+m-6=24
Multiply 3 and 8 to get 24.
m^{2}+m=24+6
Add 6 to both sides.
m^{2}+m=30
Add 24 and 6 to get 30.
m^{2}+m+\left(\frac{1}{2}\right)^{2}=30+\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}=30+\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{121}{4}
Add 30 to \frac{1}{4}.
\left(m+\frac{1}{2}\right)^{2}=\frac{121}{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{121}{4}}
Take the square root of both sides of the equation.
m+\frac{1}{2}=\frac{11}{2} m+\frac{1}{2}=-\frac{11}{2}
Simplify.
m=5 m=-6
Subtract \frac{1}{2} from both sides of the equation.
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