My teacher made me do work that i dont understand! So i need to find greatest common factors, heres what i dont understand,he put the GCF for 6 and 9 as 3, but then underneath 6…

Question

asked Feb 4, 2019 215k views

1 Answer

Padhu · Answer 1 · 2019-02-11T02:21:16+0000

To compute the GCF of two number, you need their prime factorization.

Then, you "build" the GCF by only considering the primes appearing in both factorization, with the smaller exponent possible.

So, to compute the GCF between 6 and 9, you first consider their factorization:

6 = 2 * 3

9 = 3^2 = 3 * 3

So, the only prime appearing in both factorization is 3.

It appears with exponent 1 in the factorization of 6, and with exponent 2 in the factorization of 9. We must choose the smallest, so we choose 1.

So, 3 with exponent 1 is simply 3, and here's your GCF