Polar coordinates

Polar coordinates are a way to label a point on a plane using the radius and angle, rather than x and y coordinates such as (x,y). Some important terms include: Pole=origin, polar axis=ray from the pole, r=directed distance from O to P, and lastly, Theta=angle couterclockwise from polar axis to segment OP. Unlike normal (x.y) coordinates, polar coordinates can be different yet be at the same point! What do I mean? Well, since an angle can be measured counterclockwise or clockwise, a coordinate like (r,theta) will equal (-r, theta+pi).
You should know the ways to convert coordinates from polar to rectangular. The equations you need are as follows: 

Here is an example of a conversion: