Question

Which graph shows a rate of change of one-half between –4 and 0 on the x-axis?

On a coordinate plane, a straight line with a positive slope crosses the x-axis at (6, 0) and the y-axis at (0, 3). Solid circles appear on the line at (negative 4, negative 1), (0, 3).
On a coordinate plane, a parabola opens up. It goes through (negative 5.25, 4), has a vertex of (0, negative 3), and goes through (5.25, 4). Solid circles appear on the parabola at (negative 4, 1), (0, negative 3).
On a coordinate plane, a parabola opens down. It goes through (negative 5.5, negative 4), has a vertex of (0, 4), and goes through (5.5, negative 4). Solid circles appear on the parabola at (negative 4, 0), (0, 4).
On a coordinate plane, a curved line opens up and left in quadrant 2. It is asymptotic to the negative x-axis and positive y-axis. Solid circles appear on the line at (negative 4, 0.25), (0, 4).

Answer 1

The first graph — the straight line. Between x = −4 and x = 0 the y-value goes from 1 to 3, so the average rate of change is (3 − 1)/(0 − (−4)) = 2/4 = 1/2.