19 isn't a factor of 68 and 34 isn't prime. Other than that... The largest prime factor of 68 is 17.
17
68 34,2 17,2,2
17 and 68 are not relatively prime because they have 17 as a common factor.
17
2 x 2 x 17 = 68
factor tree of 68:(68) = 2 * (34)(34) = 2 * 17so prime factors are 2 * 2 * 17
No.
68 34,2 17,2,2 2 x 2 x 17 = 68
No. 1 is not their only common factor. 17 is actually a factor of 68, so they have 1 and 17 as common factors.
68 = 2 * 2 * 17 17 + 2 = 19
2^2 x 17 = 68