There are two cases for the distributive property. For the first, let p and q be scalars and let A be a matrix. Then (p+q)A=pA+qA.
For the second case, let p be a scalar and let A and B be matrices of the same size. Then p(A+B)=pA+pB.
Example: Case 1
Let p=2, q=3 and A=[1111]
(p+q)A=(2+3)∗[1111]=5∗[1111]=[5555]
pA+qA=2∗[1111]+3∗[1111]=[2222]+[3333]=[5555]
Example: Case 2
Let p=2, A=[1111], and B=[2222]
p(A+B)=2([1111]+[2222])=2∗[3333]=[6666]
pA+pB=2∗[1111]+2∗[2222]=[2222]+[4444]=[6666]