Respuesta :

hdamr21

Answer:

3(5y-7z)

Step-by-step explanation:

3x5=15

7x3=21

Answer:

3(5y - 7z) .

Step-by-step explanation:

The GCF of 15 and 21 is 3 so:

15y - 21z = 3(5y - 7z)