Flashcard 15 - Advanced Basics Flashcard Set for the Math Basics

Why can’t these two matrices be combined(added or subtracted)?

\[\begin{bmatrix} 1 & 5 & 2 & 0\\ 1 & -3 & 9 & 1 \\ \end{bmatrix}\]

and

\[\begin{bmatrix} 0 & -6 \\ -4 & 2 \\ 2 & 3 \\ \end{bmatrix}\]