Chapter 1 - Introduction to Algebraic Expressions - 1.2 The Commutative, Associative, and Distributive Laws - 1.2 Exercise Set - Page 17: 22

$m\times 13$

The commutative law of multiplication states that $ab=ba$ (where $a$ and $b$ are real numbers). That is, changing the order of multiplication does not affect the answer. Therefore, $13m=13\times m =m\times 13$.