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# Solve the system of equations; x - 2y = 2 and 3x - 5y = 9 by writing and solving a matrix equation. Show all your work.

y=$\frac{28}{11}$ x=$\frac{3}{11}$ Working; Start by forming a matrix as shown below; $\left[\begin{array}{ccc}1&-2\\3&5\end{array}\right] ( \left[\begin{array}{ccc}x\\y\end{array}\right])= ( \left[\begin{array}{ccc}2\\9\end{array}\right])$ Step II Finding the inverse of the matrix as shown below; Determinant; (1*5)-(3*(-2)=11 Inverse; $\frac{1}{11} \left[\begin{array}{ccc}5&2\\-3&1\end{array}\right] \left[\begin{array}{ccc}1&-2\\3&5\end{array}\right] \left[\begin{array}{ccc}x\\y\end{array}\right]= \frac{1}{11} \left[\begin{array}{ccc}5&2\\-3&1\end{array}\right] \left[\begin{array}{ccc}2\\9\end{array}\right]$ Evaluating further; $\frac{1}{11} \left[\begin{array}{ccc}11&0\\0&11\end{array}\right] \left[\begin{array}{ccc}x\\y\end{array}\right] = \frac{1}{11} \left[\begin{array}{ccc}28\\3\end{array}\right]$ x=$\frac{28}{11} and y = \frac{3}{11}$