Solve for m
m=5
m=6
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m^{2}-11m=-30
Subtract 11m from both sides.
m^{2}-11m+30=0
Add 30 to both sides.
a+b=-11 ab=30
To solve the equation, factor m^{2}-11m+30 using formula m^{2}+\left(a+b\right)m+ab=\left(m+a\right)\left(m+b\right). To find a and b, set up a system to be solved.
-1,-30 -2,-15 -3,-10 -5,-6
Since ab is positive, a and b have the same sign. Since a+b is negative, a and b are both negative. List all such integer pairs that give product 30.
-1-30=-31 -2-15=-17 -3-10=-13 -5-6=-11
Calculate the sum for each pair.
a=-6 b=-5
The solution is the pair that gives sum -11.
\left(m-6\right)\left(m-5\right)
Rewrite factored expression \left(m+a\right)\left(m+b\right) using the obtained values.
m=6 m=5
To find equation solutions, solve m-6=0 and m-5=0.
m^{2}-11m=-30
Subtract 11m from both sides.
m^{2}-11m+30=0
Add 30 to both sides.
a+b=-11 ab=1\times 30=30
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as m^{2}+am+bm+30. To find a and b, set up a system to be solved.
-1,-30 -2,-15 -3,-10 -5,-6
Since ab is positive, a and b have the same sign. Since a+b is negative, a and b are both negative. List all such integer pairs that give product 30.
-1-30=-31 -2-15=-17 -3-10=-13 -5-6=-11
Calculate the sum for each pair.
a=-6 b=-5
The solution is the pair that gives sum -11.
\left(m^{2}-6m\right)+\left(-5m+30\right)
Rewrite m^{2}-11m+30 as \left(m^{2}-6m\right)+\left(-5m+30\right).
m\left(m-6\right)-5\left(m-6\right)
Factor out m in the first and -5 in the second group.
\left(m-6\right)\left(m-5\right)
Factor out common term m-6 by using distributive property.
m=6 m=5
To find equation solutions, solve m-6=0 and m-5=0.
m^{2}-11m=-30
Subtract 11m from both sides.
m^{2}-11m+30=0
Add 30 to both sides.
m=\frac{-\left(-11\right)±\sqrt{\left(-11\right)^{2}-4\times 30}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -11 for b, and 30 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
m=\frac{-\left(-11\right)±\sqrt{121-4\times 30}}{2}
Square -11.
m=\frac{-\left(-11\right)±\sqrt{121-120}}{2}
Multiply -4 times 30.
m=\frac{-\left(-11\right)±\sqrt{1}}{2}
Add 121 to -120.
m=\frac{-\left(-11\right)±1}{2}
Take the square root of 1.
m=\frac{11±1}{2}
The opposite of -11 is 11.
m=\frac{12}{2}
Now solve the equation m=\frac{11±1}{2} when ± is plus. Add 11 to 1.
m=6
Divide 12 by 2.
m=\frac{10}{2}
Now solve the equation m=\frac{11±1}{2} when ± is minus. Subtract 1 from 11.
m=5
Divide 10 by 2.
m=6 m=5
The equation is now solved.
m^{2}-11m=-30
Subtract 11m from both sides.
m^{2}-11m+\left(-\frac{11}{2}\right)^{2}=-30+\left(-\frac{11}{2}\right)^{2}
Divide -11, the coefficient of the x term, by 2 to get -\frac{11}{2}. Then add the square of -\frac{11}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
m^{2}-11m+\frac{121}{4}=-30+\frac{121}{4}
Square -\frac{11}{2} by squaring both the numerator and the denominator of the fraction.
m^{2}-11m+\frac{121}{4}=\frac{1}{4}
Add -30 to \frac{121}{4}.
\left(m-\frac{11}{2}\right)^{2}=\frac{1}{4}
Factor m^{2}-11m+\frac{121}{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{11}{2}\right)^{2}}=\sqrt{\frac{1}{4}}
Take the square root of both sides of the equation.
m-\frac{11}{2}=\frac{1}{2} m-\frac{11}{2}=-\frac{1}{2}
Simplify.
m=6 m=5
Add \frac{11}{2} to both sides of the equation.
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Limits
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