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m+24=\left(m-4\right)m
Variable m cannot be equal to any of the values -24,4 since division by zero is not defined. Multiply both sides of the equation by \left(m-4\right)\left(m+24\right), the least common multiple of m-4,m+24.
m+24=m^{2}-4m
Use the distributive property to multiply m-4 by m.
m+24-m^{2}=-4m
Subtract m^{2} from both sides.
m+24-m^{2}+4m=0
Add 4m to both sides.
5m+24-m^{2}=0
Combine m and 4m to get 5m.
-m^{2}+5m+24=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=5 ab=-24=-24
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as -m^{2}+am+bm+24. To find a and b, set up a system to be solved.
-1,24 -2,12 -3,8 -4,6
Since ab is negative, a and b have the opposite signs. Since a+b is positive, the positive number has greater absolute value than the negative. List all such integer pairs that give product -24.
-1+24=23 -2+12=10 -3+8=5 -4+6=2
Calculate the sum for each pair.
a=8 b=-3
The solution is the pair that gives sum 5.
\left(-m^{2}+8m\right)+\left(-3m+24\right)
Rewrite -m^{2}+5m+24 as \left(-m^{2}+8m\right)+\left(-3m+24\right).
-m\left(m-8\right)-3\left(m-8\right)
Factor out -m in the first and -3 in the second group.
\left(m-8\right)\left(-m-3\right)
Factor out common term m-8 by using distributive property.
m=8 m=-3
To find equation solutions, solve m-8=0 and -m-3=0.
m+24=\left(m-4\right)m
Variable m cannot be equal to any of the values -24,4 since division by zero is not defined. Multiply both sides of the equation by \left(m-4\right)\left(m+24\right), the least common multiple of m-4,m+24.
m+24=m^{2}-4m
Use the distributive property to multiply m-4 by m.
m+24-m^{2}=-4m
Subtract m^{2} from both sides.
m+24-m^{2}+4m=0
Add 4m to both sides.
5m+24-m^{2}=0
Combine m and 4m to get 5m.
-m^{2}+5m+24=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{-5±\sqrt{5^{2}-4\left(-1\right)\times 24}}{2\left(-1\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -1 for a, 5 for b, and 24 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
m=\frac{-5±\sqrt{25-4\left(-1\right)\times 24}}{2\left(-1\right)}
Square 5.
m=\frac{-5±\sqrt{25+4\times 24}}{2\left(-1\right)}
Multiply -4 times -1.
m=\frac{-5±\sqrt{25+96}}{2\left(-1\right)}
Multiply 4 times 24.
m=\frac{-5±\sqrt{121}}{2\left(-1\right)}
Add 25 to 96.
m=\frac{-5±11}{2\left(-1\right)}
Take the square root of 121.
m=\frac{-5±11}{-2}
Multiply 2 times -1.
m=\frac{6}{-2}
Now solve the equation m=\frac{-5±11}{-2} when ± is plus. Add -5 to 11.
m=-3
Divide 6 by -2.
m=-\frac{16}{-2}
Now solve the equation m=\frac{-5±11}{-2} when ± is minus. Subtract 11 from -5.
m=8
Divide -16 by -2.
m=-3 m=8
The equation is now solved.
m+24=\left(m-4\right)m
Variable m cannot be equal to any of the values -24,4 since division by zero is not defined. Multiply both sides of the equation by \left(m-4\right)\left(m+24\right), the least common multiple of m-4,m+24.
m+24=m^{2}-4m
Use the distributive property to multiply m-4 by m.
m+24-m^{2}=-4m
Subtract m^{2} from both sides.
m+24-m^{2}+4m=0
Add 4m to both sides.
5m+24-m^{2}=0
Combine m and 4m to get 5m.
5m-m^{2}=-24
Subtract 24 from both sides. Anything subtracted from zero gives its negation.
-m^{2}+5m=-24
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}+5m}{-1}=-\frac{24}{-1}
Divide both sides by -1.
m^{2}+\frac{5}{-1}m=-\frac{24}{-1}
Dividing by -1 undoes the multiplication by -1.
m^{2}-5m=-\frac{24}{-1}
Divide 5 by -1.
m^{2}-5m=24
Divide -24 by -1.
m^{2}-5m+\left(-\frac{5}{2}\right)^{2}=24+\left(-\frac{5}{2}\right)^{2}
Divide -5, the coefficient of the x term, by 2 to get -\frac{5}{2}. Then add the square of -\frac{5}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
m^{2}-5m+\frac{25}{4}=24+\frac{25}{4}
Square -\frac{5}{2} by squaring both the numerator and the denominator of the fraction.
m^{2}-5m+\frac{25}{4}=\frac{121}{4}
Add 24 to \frac{25}{4}.
\left(m-\frac{5}{2}\right)^{2}=\frac{121}{4}
Factor m^{2}-5m+\frac{25}{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{5}{2}\right)^{2}}=\sqrt{\frac{121}{4}}
Take the square root of both sides of the equation.
m-\frac{5}{2}=\frac{11}{2} m-\frac{5}{2}=-\frac{11}{2}
Simplify.
m=8 m=-3
Add \frac{5}{2} to both sides of the equation.