Question

Instead of graphing an x coordinate and y coordinate, consider r and θ where r is the distance from the origin and θ is the counterclockwise angle from what used to be the positive x axis. The coordinates r and θ  are called Polar Coordinates"
Describe the "line test" that determines whether or not a graph in polar coordinates represents a positive function r in terms of  θ, where
0≤ θ<2π