Respuesta :

7 is the GCF of 21 and 49. Does this help at all?

Answer:

The required expression is [tex]7(3m-7n)[/tex]

Step-by-step explanation:

Consider the provided expression.

[tex]21m-49n[/tex]

We need to Factor out the using the GCF.

The greatest common factor of 21 and 49 is 7.

Now reduce the expression as shown:

[tex]7(3m-7n)[/tex]

Hence, the required expression is [tex]7(3m-7n)[/tex]