Respuesta :

tramserran

Answer:  7(3m - 7n)

Step-by-step explanation:

Factor each term then see what value(s) they have in common:

          21m         -          49n

            ∧                        ∧

          3 · 7 · m              7 · 7 · n

Both terms have a 7 in common.  What is left over after removing the 7?

21m: 7(3m)

49n: 7(7n)

GCF: 7           Leftovers: 3m and  7n

Factored form of expression is: 7(3m - 7n)

sophx
As 7 is a factor of both 21 and 49, you can take out 7 from both numbers.

7(3m-7n)