Combination of diffrenet matrixes

Hello, I need to combine the following matrixes like this:

A=eye(5, 5); -> (size 5*5)

B=randi([-1 1],5 ,4); -> (size (5*4)

C=repmat(3,4,4); -> (size 4*4)

But when I typed M =[A, B; B, C] I got an error. How do I combine them?

Answer 1

[John D'Errico]

Of course you got an error. Did you write code for what you wanted? No.

This is what you wrote:

M =[A, B; B, C]

But what you claim to want to compute is:

M =[A, B; B', C]

There is a difference.