Finding Zeros
Introduction
Finding the zero(s) of a function is the result of setting the function equal to zero, or f(x) = 0. Since f(x) is the same as y, the ordered pair will be (x, f(x)) = (x, y) = (x, 0). The function crosses the x-axis when y = 0, therefore the zero of a function describes the x-intercept(s). A linear equation has no zeros or one zero.
Example Find the zero (or x-intercept) of f(x) = -2x + 4.
Step 1. Set the equation equal to 0.
-2x + 4 = 0
Step 2. Solve the equation.
-2x + 4 - 4 = 0 - 4
-2x = -4
-2 -2
x = 2
Therefore, the zero of the function is (2, 0).