Use the rational zeros theorem to write a list of all potential rational zeros f(x) = 14x^3 + 56x^2 + 2x - 7

The factors of 7are -1 and 7 or 1 and -7, the factors of 14 are 1, 2, 7, and 14, or -1,  -2, -7,-14. so the list of potential zeros are: 1/1, 1/2, 1/7, 1/14, 7/1,7/2, 7/7, 7/14, which can be simplified into 1, 1/2,1/7, 1/14, 7, 7/2
add the negative ones: -1, -1/2,-1/7, -1/14, -7, -7/2
I believe there are a total of 12 potential zeros
reference: 
http://www.sparknotes.com/math/algebra2/polynomials/section4.rhtml

Correct sir/miss have a good day x < 3

21 is the answer the answer is 21