Skip to main content
Solve for m
Tick mark Image

Similar Problems from Web Search

Share

3m^{2}+4m-3=-31-m^{2}+m
Subtract 30 from -1 to get -31.
3m^{2}+4m-3-\left(-31\right)=-m^{2}+m
Subtract -31 from both sides.
3m^{2}+4m-3+31=-m^{2}+m
The opposite of -31 is 31.
3m^{2}+4m-3+31+m^{2}=m
Add m^{2} to both sides.
3m^{2}+4m+28+m^{2}=m
Add -3 and 31 to get 28.
4m^{2}+4m+28=m
Combine 3m^{2} and m^{2} to get 4m^{2}.
4m^{2}+4m+28-m=0
Subtract m from both sides.
4m^{2}+3m+28=0
Combine 4m and -m to get 3m.
m=\frac{-3±\sqrt{3^{2}-4\times 4\times 28}}{2\times 4}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 4 for a, 3 for b, and 28 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
m=\frac{-3±\sqrt{9-4\times 4\times 28}}{2\times 4}
Square 3.
m=\frac{-3±\sqrt{9-16\times 28}}{2\times 4}
Multiply -4 times 4.
m=\frac{-3±\sqrt{9-448}}{2\times 4}
Multiply -16 times 28.
m=\frac{-3±\sqrt{-439}}{2\times 4}
Add 9 to -448.
m=\frac{-3±\sqrt{439}i}{2\times 4}
Take the square root of -439.
m=\frac{-3±\sqrt{439}i}{8}
Multiply 2 times 4.
m=\frac{-3+\sqrt{439}i}{8}
Now solve the equation m=\frac{-3±\sqrt{439}i}{8} when ± is plus. Add -3 to i\sqrt{439}.
m=\frac{-\sqrt{439}i-3}{8}
Now solve the equation m=\frac{-3±\sqrt{439}i}{8} when ± is minus. Subtract i\sqrt{439} from -3.
m=\frac{-3+\sqrt{439}i}{8} m=\frac{-\sqrt{439}i-3}{8}
The equation is now solved.
3m^{2}+4m-3=-31-m^{2}+m
Subtract 30 from -1 to get -31.
3m^{2}+4m-3+m^{2}=-31+m
Add m^{2} to both sides.
4m^{2}+4m-3=-31+m
Combine 3m^{2} and m^{2} to get 4m^{2}.
4m^{2}+4m-3-m=-31
Subtract m from both sides.
4m^{2}+3m-3=-31
Combine 4m and -m to get 3m.
4m^{2}+3m=-31+3
Add 3 to both sides.
4m^{2}+3m=-28
Add -31 and 3 to get -28.
\frac{4m^{2}+3m}{4}=-\frac{28}{4}
Divide both sides by 4.
m^{2}+\frac{3}{4}m=-\frac{28}{4}
Dividing by 4 undoes the multiplication by 4.
m^{2}+\frac{3}{4}m=-7
Divide -28 by 4.
m^{2}+\frac{3}{4}m+\left(\frac{3}{8}\right)^{2}=-7+\left(\frac{3}{8}\right)^{2}
Divide \frac{3}{4}, the coefficient of the x term, by 2 to get \frac{3}{8}. Then add the square of \frac{3}{8} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
m^{2}+\frac{3}{4}m+\frac{9}{64}=-7+\frac{9}{64}
Square \frac{3}{8} by squaring both the numerator and the denominator of the fraction.
m^{2}+\frac{3}{4}m+\frac{9}{64}=-\frac{439}{64}
Add -7 to \frac{9}{64}.
\left(m+\frac{3}{8}\right)^{2}=-\frac{439}{64}
Factor m^{2}+\frac{3}{4}m+\frac{9}{64}. 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{3}{8}\right)^{2}}=\sqrt{-\frac{439}{64}}
Take the square root of both sides of the equation.
m+\frac{3}{8}=\frac{\sqrt{439}i}{8} m+\frac{3}{8}=-\frac{\sqrt{439}i}{8}
Simplify.
m=\frac{-3+\sqrt{439}i}{8} m=\frac{-\sqrt{439}i-3}{8}
Subtract \frac{3}{8} from both sides of the equation.