Solve for m
m = -\frac{7}{5} = -1\frac{2}{5} = -1.4
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\frac{\left(3m+1\right)\left(3m-1\right)}{\left(3m-1\right)\left(-2\right)}=m+3
Variable m cannot be equal to \frac{1}{3} since division by zero is not defined. Divide \frac{3m+1}{3m-1} by \frac{-2}{3m-1} by multiplying \frac{3m+1}{3m-1} by the reciprocal of \frac{-2}{3m-1}.
\frac{\left(3m\right)^{2}-1}{\left(3m-1\right)\left(-2\right)}=m+3
Consider \left(3m+1\right)\left(3m-1\right). Multiplication can be transformed into difference of squares using the rule: \left(a-b\right)\left(a+b\right)=a^{2}-b^{2}. Square 1.
\frac{3^{2}m^{2}-1}{\left(3m-1\right)\left(-2\right)}=m+3
Expand \left(3m\right)^{2}.
\frac{9m^{2}-1}{\left(3m-1\right)\left(-2\right)}=m+3
Calculate 3 to the power of 2 and get 9.
\frac{9m^{2}-1}{-6m+2}=m+3
Use the distributive property to multiply 3m-1 by -2.
\frac{9m^{2}-1}{-6m+2}-m=3
Subtract m from both sides.
\frac{9m^{2}-1}{2\left(-3m+1\right)}-m=3
Factor -6m+2.
\frac{9m^{2}-1}{2\left(-3m+1\right)}-\frac{m\times 2\left(-3m+1\right)}{2\left(-3m+1\right)}=3
To add or subtract expressions, expand them to make their denominators the same. Multiply m times \frac{2\left(-3m+1\right)}{2\left(-3m+1\right)}.
\frac{9m^{2}-1-m\times 2\left(-3m+1\right)}{2\left(-3m+1\right)}=3
Since \frac{9m^{2}-1}{2\left(-3m+1\right)} and \frac{m\times 2\left(-3m+1\right)}{2\left(-3m+1\right)} have the same denominator, subtract them by subtracting their numerators.
\frac{9m^{2}-1+6m^{2}-2m}{2\left(-3m+1\right)}=3
Do the multiplications in 9m^{2}-1-m\times 2\left(-3m+1\right).
\frac{15m^{2}-1-2m}{2\left(-3m+1\right)}=3
Combine like terms in 9m^{2}-1+6m^{2}-2m.
\frac{15m^{2}-1-2m}{2\left(-3m+1\right)}-3=0
Subtract 3 from both sides.
\frac{15m^{2}-1-2m}{2\left(-3m+1\right)}-\frac{3\times 2\left(-3m+1\right)}{2\left(-3m+1\right)}=0
To add or subtract expressions, expand them to make their denominators the same. Multiply 3 times \frac{2\left(-3m+1\right)}{2\left(-3m+1\right)}.
\frac{15m^{2}-1-2m-3\times 2\left(-3m+1\right)}{2\left(-3m+1\right)}=0
Since \frac{15m^{2}-1-2m}{2\left(-3m+1\right)} and \frac{3\times 2\left(-3m+1\right)}{2\left(-3m+1\right)} have the same denominator, subtract them by subtracting their numerators.
\frac{15m^{2}-1-2m+18m-6}{2\left(-3m+1\right)}=0
Do the multiplications in 15m^{2}-1-2m-3\times 2\left(-3m+1\right).
\frac{15m^{2}-7+16m}{2\left(-3m+1\right)}=0
Combine like terms in 15m^{2}-1-2m+18m-6.
15m^{2}-7+16m=0
Variable m cannot be equal to \frac{1}{3} since division by zero is not defined. Multiply both sides of the equation by 2\left(-3m+1\right).
15m^{2}+16m-7=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{-16±\sqrt{16^{2}-4\times 15\left(-7\right)}}{2\times 15}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 15 for a, 16 for b, and -7 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
m=\frac{-16±\sqrt{256-4\times 15\left(-7\right)}}{2\times 15}
Square 16.
m=\frac{-16±\sqrt{256-60\left(-7\right)}}{2\times 15}
Multiply -4 times 15.
m=\frac{-16±\sqrt{256+420}}{2\times 15}
Multiply -60 times -7.
m=\frac{-16±\sqrt{676}}{2\times 15}
Add 256 to 420.
m=\frac{-16±26}{2\times 15}
Take the square root of 676.
m=\frac{-16±26}{30}
Multiply 2 times 15.
m=\frac{10}{30}
Now solve the equation m=\frac{-16±26}{30} when ± is plus. Add -16 to 26.
m=\frac{1}{3}
Reduce the fraction \frac{10}{30} to lowest terms by extracting and canceling out 10.
m=-\frac{42}{30}
Now solve the equation m=\frac{-16±26}{30} when ± is minus. Subtract 26 from -16.
m=-\frac{7}{5}
Reduce the fraction \frac{-42}{30} to lowest terms by extracting and canceling out 6.
m=\frac{1}{3} m=-\frac{7}{5}
The equation is now solved.
m=-\frac{7}{5}
Variable m cannot be equal to \frac{1}{3}.
\frac{\left(3m+1\right)\left(3m-1\right)}{\left(3m-1\right)\left(-2\right)}=m+3
Variable m cannot be equal to \frac{1}{3} since division by zero is not defined. Divide \frac{3m+1}{3m-1} by \frac{-2}{3m-1} by multiplying \frac{3m+1}{3m-1} by the reciprocal of \frac{-2}{3m-1}.
\frac{\left(3m\right)^{2}-1}{\left(3m-1\right)\left(-2\right)}=m+3
Consider \left(3m+1\right)\left(3m-1\right). Multiplication can be transformed into difference of squares using the rule: \left(a-b\right)\left(a+b\right)=a^{2}-b^{2}. Square 1.
\frac{3^{2}m^{2}-1}{\left(3m-1\right)\left(-2\right)}=m+3
Expand \left(3m\right)^{2}.
\frac{9m^{2}-1}{\left(3m-1\right)\left(-2\right)}=m+3
Calculate 3 to the power of 2 and get 9.
\frac{9m^{2}-1}{-6m+2}=m+3
Use the distributive property to multiply 3m-1 by -2.
\frac{9m^{2}-1}{-6m+2}-m=3
Subtract m from both sides.
\frac{9m^{2}-1}{2\left(-3m+1\right)}-m=3
Factor -6m+2.
\frac{9m^{2}-1}{2\left(-3m+1\right)}-\frac{m\times 2\left(-3m+1\right)}{2\left(-3m+1\right)}=3
To add or subtract expressions, expand them to make their denominators the same. Multiply m times \frac{2\left(-3m+1\right)}{2\left(-3m+1\right)}.
\frac{9m^{2}-1-m\times 2\left(-3m+1\right)}{2\left(-3m+1\right)}=3
Since \frac{9m^{2}-1}{2\left(-3m+1\right)} and \frac{m\times 2\left(-3m+1\right)}{2\left(-3m+1\right)} have the same denominator, subtract them by subtracting their numerators.
\frac{9m^{2}-1+6m^{2}-2m}{2\left(-3m+1\right)}=3
Do the multiplications in 9m^{2}-1-m\times 2\left(-3m+1\right).
\frac{15m^{2}-1-2m}{2\left(-3m+1\right)}=3
Combine like terms in 9m^{2}-1+6m^{2}-2m.
15m^{2}-1-2m=6\left(-3m+1\right)
Variable m cannot be equal to \frac{1}{3} since division by zero is not defined. Multiply both sides of the equation by 2\left(-3m+1\right).
15m^{2}-1-2m=-18m+6
Use the distributive property to multiply 6 by -3m+1.
15m^{2}-1-2m+18m=6
Add 18m to both sides.
15m^{2}-1+16m=6
Combine -2m and 18m to get 16m.
15m^{2}+16m=6+1
Add 1 to both sides.
15m^{2}+16m=7
Add 6 and 1 to get 7.
\frac{15m^{2}+16m}{15}=\frac{7}{15}
Divide both sides by 15.
m^{2}+\frac{16}{15}m=\frac{7}{15}
Dividing by 15 undoes the multiplication by 15.
m^{2}+\frac{16}{15}m+\left(\frac{8}{15}\right)^{2}=\frac{7}{15}+\left(\frac{8}{15}\right)^{2}
Divide \frac{16}{15}, the coefficient of the x term, by 2 to get \frac{8}{15}. Then add the square of \frac{8}{15} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
m^{2}+\frac{16}{15}m+\frac{64}{225}=\frac{7}{15}+\frac{64}{225}
Square \frac{8}{15} by squaring both the numerator and the denominator of the fraction.
m^{2}+\frac{16}{15}m+\frac{64}{225}=\frac{169}{225}
Add \frac{7}{15} to \frac{64}{225} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(m+\frac{8}{15}\right)^{2}=\frac{169}{225}
Factor m^{2}+\frac{16}{15}m+\frac{64}{225}. 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{8}{15}\right)^{2}}=\sqrt{\frac{169}{225}}
Take the square root of both sides of the equation.
m+\frac{8}{15}=\frac{13}{15} m+\frac{8}{15}=-\frac{13}{15}
Simplify.
m=\frac{1}{3} m=-\frac{7}{5}
Subtract \frac{8}{15} from both sides of the equation.
m=-\frac{7}{5}
Variable m cannot be equal to \frac{1}{3}.
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Limits
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