Adding two matrices of different sizes?

A=[1 2 3 4;8 7 9 6 ;4 5 6 1]
B=[4 8 9 8 ;1 2 3 4 ]

how can i add A and B?

[Adam]

What exactly are you expecting the result of such an addition to be? Define 'addition' in this context and give the expected result and it will likely be trivial. Otherwise, there is no definition of addition that I am aware of that works on different sized matrices of that form.

[KSSV]

YOu have to extend B's size to A either by padding zeros at first row or end row and then add.

[Stephen23]

@ Bibhu Prasad Pala: of course this can be done, once you define what you mean by "Adding two matrices of different sizes". For example, matrix A has three rows, but matrix B has only two rows: what would you expect the values in the third row of A to be added to?