Question

If matrix A has dimensions 4 x 1 and matrix B has dimensions 1 x 5, can matrix A and matrix B be multiplied?

yes

no

Answer 1

for matrix multiplication the inner dimensions must be equal

so looking at your problem we have:

(4 x 1) x (1 x 5)

are the inner dimensions equal?

Answer 2

yes

Answer 3

awesome, so the solution would be "yes" they can be multiplied