### Home > PC3 > Chapter 12 > Lesson 12.1.4 > Problem12-60

12-60.

Write the equation of each conic described below.

1. A circle centered at $(5, 1)$ with a circumference of $40π$.

If the circumference of a circle is $2πr$, what is the radius of this circle?

2. An ellipse that has foci at $(3, 0)$ and $(−3, 0)$ and a major axis of length $10$.

The center of the ellipse lies at the midpoint of the two foci.