Solve for m
m = \frac{12}{5} = 2\frac{2}{5} = 2.4
m=0
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m\left(\frac{5}{6}m-2\right)=0
Factor out m.
m=0 m=\frac{12}{5}
To find equation solutions, solve m=0 and \frac{5m}{6}-2=0.
\frac{5}{6}m^{2}-2m=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{-\left(-2\right)±\sqrt{\left(-2\right)^{2}}}{2\times \frac{5}{6}}
This equation is in standard form: ax^{2}+bx+c=0. Substitute \frac{5}{6} for a, -2 for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
m=\frac{-\left(-2\right)±2}{2\times \frac{5}{6}}
Take the square root of \left(-2\right)^{2}.
m=\frac{2±2}{2\times \frac{5}{6}}
The opposite of -2 is 2.
m=\frac{2±2}{\frac{5}{3}}
Multiply 2 times \frac{5}{6}.
m=\frac{4}{\frac{5}{3}}
Now solve the equation m=\frac{2±2}{\frac{5}{3}} when ± is plus. Add 2 to 2.
m=\frac{12}{5}
Divide 4 by \frac{5}{3} by multiplying 4 by the reciprocal of \frac{5}{3}.
m=\frac{0}{\frac{5}{3}}
Now solve the equation m=\frac{2±2}{\frac{5}{3}} when ± is minus. Subtract 2 from 2.
m=0
Divide 0 by \frac{5}{3} by multiplying 0 by the reciprocal of \frac{5}{3}.
m=\frac{12}{5} m=0
The equation is now solved.
\frac{5}{6}m^{2}-2m=0
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{\frac{5}{6}m^{2}-2m}{\frac{5}{6}}=\frac{0}{\frac{5}{6}}
Divide both sides of the equation by \frac{5}{6}, which is the same as multiplying both sides by the reciprocal of the fraction.
m^{2}+\left(-\frac{2}{\frac{5}{6}}\right)m=\frac{0}{\frac{5}{6}}
Dividing by \frac{5}{6} undoes the multiplication by \frac{5}{6}.
m^{2}-\frac{12}{5}m=\frac{0}{\frac{5}{6}}
Divide -2 by \frac{5}{6} by multiplying -2 by the reciprocal of \frac{5}{6}.
m^{2}-\frac{12}{5}m=0
Divide 0 by \frac{5}{6} by multiplying 0 by the reciprocal of \frac{5}{6}.
m^{2}-\frac{12}{5}m+\left(-\frac{6}{5}\right)^{2}=\left(-\frac{6}{5}\right)^{2}
Divide -\frac{12}{5}, the coefficient of the x term, by 2 to get -\frac{6}{5}. Then add the square of -\frac{6}{5} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
m^{2}-\frac{12}{5}m+\frac{36}{25}=\frac{36}{25}
Square -\frac{6}{5} by squaring both the numerator and the denominator of the fraction.
\left(m-\frac{6}{5}\right)^{2}=\frac{36}{25}
Factor m^{2}-\frac{12}{5}m+\frac{36}{25}. 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{6}{5}\right)^{2}}=\sqrt{\frac{36}{25}}
Take the square root of both sides of the equation.
m-\frac{6}{5}=\frac{6}{5} m-\frac{6}{5}=-\frac{6}{5}
Simplify.
m=\frac{12}{5} m=0
Add \frac{6}{5} to both sides of the equation.
Examples
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{ 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}