TI-83 users:

To delete any existing matrices from memory, follow these steps carefully!

2nd MEM key. 2: menu selection. 5: menu selection.

Press ENTER key. repeatedly until no more matrix names are listed.

2nd QUIT key.

Now you are ready to enter matrix A.

TI-83/84 Plus users:

To delete any existing matrices from memory, follow these steps carefully!

2nd MEM key. 2: menu selection. 5: menu selection.

Press DEL key. repeatedly until no more matrix names are listed.

2nd QUIT key.

Now you are ready to enter matrix A.