Answer
$$\begin{pmatrix}-\frac{4}{3}&\frac{4}{3}&-\frac{1}{3}\\ -\frac{5}{6}&\frac{1}{3}&\frac{1}{6}\\ \frac{7}{6}&-\frac{2}{3}&\frac{1}{6}\end{pmatrix}$$
Work Step by Step
To use a graphing calculator to find the inverse of a Matrix, first select (2nd) and ($x^{-1})$ to bring up the Matrix menu. Next, scroll to edit, select Matrix [A], and plug in the given Matrix. (You may have to change the dimensions of the Matrix.) Finally, going back to the main screen, select (2nd) and ($x^{-1})$. Then, choose Matrix A, and press the $x^{-1}$ to find its inverse. Doing this, we find:
$$\begin{pmatrix}-\frac{4}{3}&\frac{4}{3}&-\frac{1}{3}\\ -\frac{5}{6}&\frac{1}{3}&\frac{1}{6}\\ \frac{7}{6}&-\frac{2}{3}&\frac{1}{6}\end{pmatrix}$$