Write the equation of a circle given the center and tangent to origin

The video tutorial explains the equation of a circle, focusing on its center and radius. It discusses how to graph a circle and the concept of tangency, where a circle touches the origin at a single point. The tutorial further explores the concept of radius, emphasizing its uniformity around the circle. It concludes with a calculation of the radius using the Pythagorean theorem, demonstrating how to find the radius when given specific coordinates.

Describe the relationship between the center of a circle and its radius.

How can you determine the radius of a circle using the Pythagorean theorem?