#### Answer

The foundation of a polar coordinate system consists of a point called a
pole and a ray extended called the polar axis.

#### Work Step by Step

The pole is the foundation of the polar coordinate system and the polar axis is the ray extended out from this point in any of the directions; it is extended in either the positive or negative x-axis or in the positive or negative y-axis.
Here, in the given example, the polar axis is extended in the positive x-direction.