Solve for m
m=8
m=0
Share
Copied to clipboard
m^{2}+11m+30=\left(m+3\right)\left(m+10\right)+\left(m-10\right)m
Variable m cannot be equal to any of the values -3,10 since division by zero is not defined. Multiply both sides of the equation by 4\left(m-10\right)\left(m+3\right), the least common multiple of 4m^{2}-28m-120,4m-40,4m+12.
m^{2}+11m+30=m^{2}+13m+30+\left(m-10\right)m
Use the distributive property to multiply m+3 by m+10 and combine like terms.
m^{2}+11m+30=m^{2}+13m+30+m^{2}-10m
Use the distributive property to multiply m-10 by m.
m^{2}+11m+30=2m^{2}+13m+30-10m
Combine m^{2} and m^{2} to get 2m^{2}.
m^{2}+11m+30=2m^{2}+3m+30
Combine 13m and -10m to get 3m.
m^{2}+11m+30-2m^{2}=3m+30
Subtract 2m^{2} from both sides.
-m^{2}+11m+30=3m+30
Combine m^{2} and -2m^{2} to get -m^{2}.
-m^{2}+11m+30-3m=30
Subtract 3m from both sides.
-m^{2}+8m+30=30
Combine 11m and -3m to get 8m.
-m^{2}+8m+30-30=0
Subtract 30 from both sides.
-m^{2}+8m=0
Subtract 30 from 30 to get 0.
m\left(-m+8\right)=0
Factor out m.
m=0 m=8
To find equation solutions, solve m=0 and -m+8=0.
m^{2}+11m+30=\left(m+3\right)\left(m+10\right)+\left(m-10\right)m
Variable m cannot be equal to any of the values -3,10 since division by zero is not defined. Multiply both sides of the equation by 4\left(m-10\right)\left(m+3\right), the least common multiple of 4m^{2}-28m-120,4m-40,4m+12.
m^{2}+11m+30=m^{2}+13m+30+\left(m-10\right)m
Use the distributive property to multiply m+3 by m+10 and combine like terms.
m^{2}+11m+30=m^{2}+13m+30+m^{2}-10m
Use the distributive property to multiply m-10 by m.
m^{2}+11m+30=2m^{2}+13m+30-10m
Combine m^{2} and m^{2} to get 2m^{2}.
m^{2}+11m+30=2m^{2}+3m+30
Combine 13m and -10m to get 3m.
m^{2}+11m+30-2m^{2}=3m+30
Subtract 2m^{2} from both sides.
-m^{2}+11m+30=3m+30
Combine m^{2} and -2m^{2} to get -m^{2}.
-m^{2}+11m+30-3m=30
Subtract 3m from both sides.
-m^{2}+8m+30=30
Combine 11m and -3m to get 8m.
-m^{2}+8m+30-30=0
Subtract 30 from both sides.
-m^{2}+8m=0
Subtract 30 from 30 to get 0.
m=\frac{-8±\sqrt{8^{2}}}{2\left(-1\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -1 for a, 8 for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
m=\frac{-8±8}{2\left(-1\right)}
Take the square root of 8^{2}.
m=\frac{-8±8}{-2}
Multiply 2 times -1.
m=\frac{0}{-2}
Now solve the equation m=\frac{-8±8}{-2} when ± is plus. Add -8 to 8.
m=0
Divide 0 by -2.
m=-\frac{16}{-2}
Now solve the equation m=\frac{-8±8}{-2} when ± is minus. Subtract 8 from -8.
m=8
Divide -16 by -2.
m=0 m=8
The equation is now solved.
m^{2}+11m+30=\left(m+3\right)\left(m+10\right)+\left(m-10\right)m
Variable m cannot be equal to any of the values -3,10 since division by zero is not defined. Multiply both sides of the equation by 4\left(m-10\right)\left(m+3\right), the least common multiple of 4m^{2}-28m-120,4m-40,4m+12.
m^{2}+11m+30=m^{2}+13m+30+\left(m-10\right)m
Use the distributive property to multiply m+3 by m+10 and combine like terms.
m^{2}+11m+30=m^{2}+13m+30+m^{2}-10m
Use the distributive property to multiply m-10 by m.
m^{2}+11m+30=2m^{2}+13m+30-10m
Combine m^{2} and m^{2} to get 2m^{2}.
m^{2}+11m+30=2m^{2}+3m+30
Combine 13m and -10m to get 3m.
m^{2}+11m+30-2m^{2}=3m+30
Subtract 2m^{2} from both sides.
-m^{2}+11m+30=3m+30
Combine m^{2} and -2m^{2} to get -m^{2}.
-m^{2}+11m+30-3m=30
Subtract 3m from both sides.
-m^{2}+8m+30=30
Combine 11m and -3m to get 8m.
-m^{2}+8m=30-30
Subtract 30 from both sides.
-m^{2}+8m=0
Subtract 30 from 30 to get 0.
\frac{-m^{2}+8m}{-1}=\frac{0}{-1}
Divide both sides by -1.
m^{2}+\frac{8}{-1}m=\frac{0}{-1}
Dividing by -1 undoes the multiplication by -1.
m^{2}-8m=\frac{0}{-1}
Divide 8 by -1.
m^{2}-8m=0
Divide 0 by -1.
m^{2}-8m+\left(-4\right)^{2}=\left(-4\right)^{2}
Divide -8, the coefficient of the x term, by 2 to get -4. Then add the square of -4 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
m^{2}-8m+16=16
Square -4.
\left(m-4\right)^{2}=16
Factor m^{2}-8m+16. 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-4\right)^{2}}=\sqrt{16}
Take the square root of both sides of the equation.
m-4=4 m-4=-4
Simplify.
m=8 m=0
Add 4 to both sides of the equation.
Examples
Quadratic equation
{ x } ^ { 2 } - 4 x - 5 = 0
Trigonometry
4 \sin \theta \cos \theta = 2 \sin \theta
Linear equation
y = 3x + 4
Arithmetic
699 * 533
Matrix
\left[ \begin{array} { l l } { 2 } & { 3 } \\ { 5 } & { 4 } \end{array} \right] \left[ \begin{array} { l l l } { 2 } & { 0 } & { 3 } \\ { -1 } & { 1 } & { 5 } \end{array} \right]
Simultaneous equation
\left. \begin{cases} { 8x+2y = 46 } \\ { 7x+3y = 47 } \end{cases} \right.
Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
\int _ { 0 } ^ { 1 } x e ^ { - x ^ { 2 } } d x
Limits
\lim _{x \rightarrow-3} \frac{x^{2}-9}{x^{2}+2 x-3}