what is the greatest common factor of 49 and 84?
['The prime factorization of 49 is: 7 x 7.', 'The prime factorization of 84 is: 2 x 2 x 3 x 7.', 'The prime factors and multiplicities 49 and 84 have in common are: 7.', '7 is the gcf of 49 and 84.', 'gcf(49,84) = 7.']