Which of the following polynomials is a binomial?

A) 6x

B) 5x-9

C) X^2 + 8x - 3

D) 2x^3 + 4x^2-7x+1

A binomial is a type of a polynomial which only has two terms. The name of the type of polynomial suggests that it must have only 2 terms. From the given equations in the choices, the one which has only 2 terms is the second option. Hence, the answer is letter B.