Which of the following is a factor of 3a^2-17a+20? And why?

Question

 Sorry made mistake when I originally asked question:

A. 3a-20

B. a-4

C. a+4

D. 3a+5

Answer 1

When you completely factor the polynomial you will get: (3a-5)(a-4)

If you are using the grouping method, the factorization will look like:

 

3a^2-17a+20

3a^2-12a-5a+20

(3a^2-12a)+(-5a+20)

3a(a-4)-5(a-4) <--factor out 3a and -5 respectively, (a-4) is now a common term

(3a-5)(a-4)