What is the gcf of -126 168 210?

Answer 1

Factor out each term to get:

126 = 3 x 42

= 3 x 3 x 14

= 3² x 2 x 7

168 = 4 x 42

= 2² x 3 x 2 x 7

= 2³ x 3 x 7

210 = 10 x 21

= 2 x 5 x 3 x 7

So the GCF is 2 x 3 x 7 = 42 since that is the greatest multiple that divide 126, 168 and 210..