Matrix Math with VBA (System of Linear Equations)

Two things:

The same rule applies as in actual mathematics: B must be a vertical array for matrix multiplication to be possible in your case. Declare it as

Dim B(0 To 1, 0 To 0) As Single

and initialize it accordingly. Also, just declare

Dim X As Variant

since the MMult returns a Variant array. This is what was causing your original error.

CodeHunter