Question

What is the equation of a circle whose center is at the origin and whose radius is 16?

Answer 1

Polar form: r = 16.
Cartesian form: r = `sqrt(x^2+y^2)` = 16 or `(x^2+y^2)` = `16^2`

Explanation:

Points on a circle are equidistant from its center. This distance is called the radius of the circle.