Decide Whether or Not the Matrices Are Inverses of Each $\left[ \begin{array} { c c } - 5 & 1 \\ - 7 & 1 \end{array} \right]$

Decide whether or not the matrices are inverses of each other.
- $\left[ \begin{array} { c c } - 5 & 1 \\ - 7 & 1 \end{array} \right]$ and $\left[ \begin{array} { l } \frac { 1 } { 2 } - \frac { 1 } { 2 } \\ \frac { 7 } { 2 } - \frac { 5 } { 2 } \end{array} \right]$

A) No
B) Yes