Respuesta :
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]