Solve for m
m=-1
m=6
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\frac{1}{5}m^{2}-\frac{6}{5}=m
Divide each term of m^{2}-6 by 5 to get \frac{1}{5}m^{2}-\frac{6}{5}.
\frac{1}{5}m^{2}-\frac{6}{5}-m=0
Subtract m from both sides.
\frac{1}{5}m^{2}-m-\frac{6}{5}=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(-1\right)±\sqrt{1-4\times \frac{1}{5}\left(-\frac{6}{5}\right)}}{2\times \frac{1}{5}}
This equation is in standard form: ax^{2}+bx+c=0. Substitute \frac{1}{5} for a, -1 for b, and -\frac{6}{5} for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
m=\frac{-\left(-1\right)±\sqrt{1-\frac{4}{5}\left(-\frac{6}{5}\right)}}{2\times \frac{1}{5}}
Multiply -4 times \frac{1}{5}.
m=\frac{-\left(-1\right)±\sqrt{1+\frac{24}{25}}}{2\times \frac{1}{5}}
Multiply -\frac{4}{5} times -\frac{6}{5} by multiplying numerator times numerator and denominator times denominator. Then reduce the fraction to lowest terms if possible.
m=\frac{-\left(-1\right)±\sqrt{\frac{49}{25}}}{2\times \frac{1}{5}}
Add 1 to \frac{24}{25}.
m=\frac{-\left(-1\right)±\frac{7}{5}}{2\times \frac{1}{5}}
Take the square root of \frac{49}{25}.
m=\frac{1±\frac{7}{5}}{2\times \frac{1}{5}}
The opposite of -1 is 1.
m=\frac{1±\frac{7}{5}}{\frac{2}{5}}
Multiply 2 times \frac{1}{5}.
m=\frac{\frac{12}{5}}{\frac{2}{5}}
Now solve the equation m=\frac{1±\frac{7}{5}}{\frac{2}{5}} when ± is plus. Add 1 to \frac{7}{5}.
m=6
Divide \frac{12}{5} by \frac{2}{5} by multiplying \frac{12}{5} by the reciprocal of \frac{2}{5}.
m=-\frac{\frac{2}{5}}{\frac{2}{5}}
Now solve the equation m=\frac{1±\frac{7}{5}}{\frac{2}{5}} when ± is minus. Subtract \frac{7}{5} from 1.
m=-1
Divide -\frac{2}{5} by \frac{2}{5} by multiplying -\frac{2}{5} by the reciprocal of \frac{2}{5}.
m=6 m=-1
The equation is now solved.
\frac{1}{5}m^{2}-\frac{6}{5}=m
Divide each term of m^{2}-6 by 5 to get \frac{1}{5}m^{2}-\frac{6}{5}.
\frac{1}{5}m^{2}-\frac{6}{5}-m=0
Subtract m from both sides.
\frac{1}{5}m^{2}-m=\frac{6}{5}
Add \frac{6}{5} to both sides. Anything plus zero gives itself.
\frac{\frac{1}{5}m^{2}-m}{\frac{1}{5}}=\frac{\frac{6}{5}}{\frac{1}{5}}
Multiply both sides by 5.
m^{2}+\left(-\frac{1}{\frac{1}{5}}\right)m=\frac{\frac{6}{5}}{\frac{1}{5}}
Dividing by \frac{1}{5} undoes the multiplication by \frac{1}{5}.
m^{2}-5m=\frac{\frac{6}{5}}{\frac{1}{5}}
Divide -1 by \frac{1}{5} by multiplying -1 by the reciprocal of \frac{1}{5}.
m^{2}-5m=6
Divide \frac{6}{5} by \frac{1}{5} by multiplying \frac{6}{5} by the reciprocal of \frac{1}{5}.
m^{2}-5m+\left(-\frac{5}{2}\right)^{2}=6+\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}=6+\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{49}{4}
Add 6 to \frac{25}{4}.
\left(m-\frac{5}{2}\right)^{2}=\frac{49}{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{49}{4}}
Take the square root of both sides of the equation.
m-\frac{5}{2}=\frac{7}{2} m-\frac{5}{2}=-\frac{7}{2}
Simplify.
m=6 m=-1
Add \frac{5}{2} to both sides of the equation.
Examples
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{ x } ^ { 2 } - 4 x - 5 = 0
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Linear equation
y = 3x + 4
Arithmetic
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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}