The function is decreasing on the interval (-∞,∞)
This means that, throughout the whole graph, the slope is negative.
Addition,subtraction,and multiplication
Circumference = pi x diameter
So for this it is
36 = 3.14 x d (d = r x 2)
36 / 3.14 = 2r
11.46 = 2r
11.46 / 2 = r
5.73 = r
