What is a compatibility matrix?
Compatible matrices are matrices which can be multiplied. For this to be possible, the number of columns in the first matrix must be equal to the number of rows in the second matrix. The product of an a×b matrix and a b×c matrix has dimensions a×c .
How do you know if a matrix is compatible?
Two matrices are compatible (for multiplication) if the number of columns in the first equals the number of rows in the second. This is because each row (with j elements) in the first matrix will be multiplied by each column (with i elements) in the second matrix.