Texas Instruments TI-73 Software Manual page 24

Multiplying a matrix by a value or a value by a matrix returns a
matrix in which each element of matrix is multiplied by value .
¦
matrix value
¦
value matrix
– (Negation)
a
Returns a matrix in which the sign of every element is changed
(reversed).
L
matrix
Matrices for the TI-73 Page 24