Detailed description

4 graphs.
  1. Circle, centre the origin of radius 5, with equation x squared  plus y squared = 25.
  2. Ellipse with centre the origin with equation x squared over 16 + y squared over 9 = 1.
  3. Two straight lines passing through the origin with equation y squared = x squared.
  4. Hyperbola with equation x squared over 16 – y squared over 9 = 1.