Can We Subtract Matrices with Different Dimensions?

[Quarlep]

We have a matrix A4x5 and B2x3 can we remove(-) them A-B

Thanks

 

[HallsofIvy]

That depends upon what you mean by "remove". Normally "-" means "subtract". That is defined only for matrices with the same number of rows and columns.

If you mean $a_{ij}- b_{ij}$, taking $b_{ij}= 0$ if i> 2 and j> 3, you can define that (you can define anything) but it will not obey any of the usual algebraic rules- so probably won't be of much use.