Relax

Respuesta :

a. The GCF of 18 and 21 is 3.

18 +21 = 6 x 3 + 7 x 3 = 3(6 + 7)

b. The GCF of 56 and 35 is 7.

56 + 35 = 7(8 + 5)

Hope I helped!