Beginning & Intermediate Algebra
All points whose x‑coordinate equals h and whose y‑coordinate is within r units of k.
The set of ordered pairs (x,y) such that (x–h)2 + (y–k)2 < r2, after translation by (h,k).
All points whose average distance from (h,k) over any interval is equal to r.
The set of all points in the plane that are exactly distance r from the point (h,k).