Solve for n
n=-5
n=10
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\frac{1}{12}\left(n-3\right)\left(n-2\right)\times 3=14
Variable n cannot be equal to any of the values 2,3 since division by zero is not defined. Multiply both sides of the equation by 2\left(n-3\right)\left(n-2\right).
\left(\frac{1}{12}n-\frac{1}{4}\right)\left(n-2\right)\times 3=14
Use the distributive property to multiply \frac{1}{12} by n-3.
\left(\frac{1}{12}n^{2}-\frac{5}{12}n+\frac{1}{2}\right)\times 3=14
Use the distributive property to multiply \frac{1}{12}n-\frac{1}{4} by n-2 and combine like terms.
\frac{1}{4}n^{2}-\frac{5}{4}n+\frac{3}{2}=14
Use the distributive property to multiply \frac{1}{12}n^{2}-\frac{5}{12}n+\frac{1}{2} by 3.
\frac{1}{4}n^{2}-\frac{5}{4}n+\frac{3}{2}-14=0
Subtract 14 from both sides.
\frac{1}{4}n^{2}-\frac{5}{4}n-\frac{25}{2}=0
Subtract 14 from \frac{3}{2} to get -\frac{25}{2}.
n=\frac{-\left(-\frac{5}{4}\right)±\sqrt{\left(-\frac{5}{4}\right)^{2}-4\times \frac{1}{4}\left(-\frac{25}{2}\right)}}{2\times \frac{1}{4}}
This equation is in standard form: ax^{2}+bx+c=0. Substitute \frac{1}{4} for a, -\frac{5}{4} for b, and -\frac{25}{2} for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
n=\frac{-\left(-\frac{5}{4}\right)±\sqrt{\frac{25}{16}-4\times \frac{1}{4}\left(-\frac{25}{2}\right)}}{2\times \frac{1}{4}}
Square -\frac{5}{4} by squaring both the numerator and the denominator of the fraction.
n=\frac{-\left(-\frac{5}{4}\right)±\sqrt{\frac{25}{16}-\left(-\frac{25}{2}\right)}}{2\times \frac{1}{4}}
Multiply -4 times \frac{1}{4}.
n=\frac{-\left(-\frac{5}{4}\right)±\sqrt{\frac{25}{16}+\frac{25}{2}}}{2\times \frac{1}{4}}
Multiply -1 times -\frac{25}{2}.
n=\frac{-\left(-\frac{5}{4}\right)±\sqrt{\frac{225}{16}}}{2\times \frac{1}{4}}
Add \frac{25}{16} to \frac{25}{2} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
n=\frac{-\left(-\frac{5}{4}\right)±\frac{15}{4}}{2\times \frac{1}{4}}
Take the square root of \frac{225}{16}.
n=\frac{\frac{5}{4}±\frac{15}{4}}{2\times \frac{1}{4}}
The opposite of -\frac{5}{4} is \frac{5}{4}.
n=\frac{\frac{5}{4}±\frac{15}{4}}{\frac{1}{2}}
Multiply 2 times \frac{1}{4}.
n=\frac{5}{\frac{1}{2}}
Now solve the equation n=\frac{\frac{5}{4}±\frac{15}{4}}{\frac{1}{2}} when ± is plus. Add \frac{5}{4} to \frac{15}{4} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
n=10
Divide 5 by \frac{1}{2} by multiplying 5 by the reciprocal of \frac{1}{2}.
n=-\frac{\frac{5}{2}}{\frac{1}{2}}
Now solve the equation n=\frac{\frac{5}{4}±\frac{15}{4}}{\frac{1}{2}} when ± is minus. Subtract \frac{15}{4} from \frac{5}{4} by finding a common denominator and subtracting the numerators. Then reduce the fraction to lowest terms if possible.
n=-5
Divide -\frac{5}{2} by \frac{1}{2} by multiplying -\frac{5}{2} by the reciprocal of \frac{1}{2}.
n=10 n=-5
The equation is now solved.
\frac{1}{12}\left(n-3\right)\left(n-2\right)\times 3=14
Variable n cannot be equal to any of the values 2,3 since division by zero is not defined. Multiply both sides of the equation by 2\left(n-3\right)\left(n-2\right).
\left(\frac{1}{12}n-\frac{1}{4}\right)\left(n-2\right)\times 3=14
Use the distributive property to multiply \frac{1}{12} by n-3.
\left(\frac{1}{12}n^{2}-\frac{5}{12}n+\frac{1}{2}\right)\times 3=14
Use the distributive property to multiply \frac{1}{12}n-\frac{1}{4} by n-2 and combine like terms.
\frac{1}{4}n^{2}-\frac{5}{4}n+\frac{3}{2}=14
Use the distributive property to multiply \frac{1}{12}n^{2}-\frac{5}{12}n+\frac{1}{2} by 3.
\frac{1}{4}n^{2}-\frac{5}{4}n=14-\frac{3}{2}
Subtract \frac{3}{2} from both sides.
\frac{1}{4}n^{2}-\frac{5}{4}n=\frac{25}{2}
Subtract \frac{3}{2} from 14 to get \frac{25}{2}.
\frac{\frac{1}{4}n^{2}-\frac{5}{4}n}{\frac{1}{4}}=\frac{\frac{25}{2}}{\frac{1}{4}}
Multiply both sides by 4.
n^{2}+\left(-\frac{\frac{5}{4}}{\frac{1}{4}}\right)n=\frac{\frac{25}{2}}{\frac{1}{4}}
Dividing by \frac{1}{4} undoes the multiplication by \frac{1}{4}.
n^{2}-5n=\frac{\frac{25}{2}}{\frac{1}{4}}
Divide -\frac{5}{4} by \frac{1}{4} by multiplying -\frac{5}{4} by the reciprocal of \frac{1}{4}.
n^{2}-5n=50
Divide \frac{25}{2} by \frac{1}{4} by multiplying \frac{25}{2} by the reciprocal of \frac{1}{4}.
n^{2}-5n+\left(-\frac{5}{2}\right)^{2}=50+\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.
n^{2}-5n+\frac{25}{4}=50+\frac{25}{4}
Square -\frac{5}{2} by squaring both the numerator and the denominator of the fraction.
n^{2}-5n+\frac{25}{4}=\frac{225}{4}
Add 50 to \frac{25}{4}.
\left(n-\frac{5}{2}\right)^{2}=\frac{225}{4}
Factor n^{2}-5n+\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(n-\frac{5}{2}\right)^{2}}=\sqrt{\frac{225}{4}}
Take the square root of both sides of the equation.
n-\frac{5}{2}=\frac{15}{2} n-\frac{5}{2}=-\frac{15}{2}
Simplify.
n=10 n=-5
Add \frac{5}{2} to both sides of the equation.
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