Zeros of a function
The zeros of a function, also referred to as roots or x-intercepts, occur at x-values where f(x) = 0. Not all functions have zeros.
You can find the zeros of a function by setting that function equal to 0 and solving for x. The easiest way to find the zeros of a polynomial is by factoring. For quadratics, you can use the quadratic formula.
On a graph, the zeros of a function occur when the curve crosses the x-axis. Therefore, all zeros will have a coordinate of form (x, 0).
The graph below has zeros at x = -5, -1, 3