Matrix Equality
To understand matrix algebra, we need to understand matrix equality. Two matrices are equal if all three of the following conditions are met:
Each matrix has the same number of rows.
Each matrix has the same number of columns.
Corresponding elements within each matrix are equal.
Consider the three matrices shown below.
A =
111 x
y 444
B =
111 222
333 444
C =
l m n
o p q
If A = B, we know that x = 222 and y = 333; since corresponding elements of equal matrices are also equal. And we know that matrix C is not equal to A or B, because C has more columns than A or B.