\left\{ \begin{array} { l } { a _ { n } = - \frac { 3 ( n - 1 ) } { 3 - 2 n } } \\ { n = 4 } \end{array} \right.
Solve for a_n, n
a_{n} = \frac{9}{5} = 1\frac{4}{5} = 1.8
n=4
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a_{n}=-\frac{3\left(4-1\right)}{3-2\times 4}
Consider the first equation. Insert the known values of variables into the equation.
a_{n}=-\frac{3\times 3}{3-2\times 4}
Subtract 1 from 4 to get 3.
a_{n}=-\frac{9}{3-2\times 4}
Multiply 3 and 3 to get 9.
a_{n}=-\frac{9}{3-8}
Multiply -2 and 4 to get -8.
a_{n}=-\frac{9}{-5}
Subtract 8 from 3 to get -5.
a_{n}=-\left(-\frac{9}{5}\right)
Fraction \frac{9}{-5} can be rewritten as -\frac{9}{5} by extracting the negative sign.
a_{n}=\frac{9}{5}
The opposite of -\frac{9}{5} is \frac{9}{5}.
a_{n}=\frac{9}{5} n=4
The system is now solved.
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