### Home > INT3 > Chapter 12 > Lesson 12.1.3 > Problem 12-48

12-48.

A circle with its center on the line in the first quadrant is tangent to the

*‑axis.*

If the radius is

, what is the equation of the circle? What point on the line

isunits from the -axis?Use the coordinates of the center and the radius to write an equation in general form.

If the radius is

, what is the equation of the circle? See part (a).

Use the eTool below for help with this problem.

Click on the link at right for the full eTool version:*Int3 12-48 HW eTool*