You have probably learned that a
zero of a function
f(x) is any value
c such that
f(c)=0. When the function is graphed, the real zeros of the function are the x-intercepts of the graph.
If

is a polynomial function, then
c is a zero of the polynomial function f(x),
x-c is a factor of the polynomial function f(x), and
c is a root or solution of the polynomial equation f(x)=0.