My sweet husband cut out the 3 elliptical pool tables from our left over shelving material. I wasn't home when he did them.
The first one went fine. He just cut along the outline my 1st period made. He also did the 2nd one, but felt the outline was too close to the edge (within an inch), but cut it anyway. On the 3rd one, he decided to cut uniformly about 1/2" in from the outline of the ellipse because again, he felt it was too close to the edge.
Well, unexpected, but a great question for the students: is this new shape still an ellipse by definition? I posed it to them on Tuesday without resolving the issue. I'll let them stew over it (or in most likelyhood forget about it) while I'm gone for 3 days .......... to the NCTM conference in St. Louis.
When I get back, we'll try out the tables and see how accurately we can shoot from one focal point anywhere along the edge to see if it bounces back to the other focal point. Tres exciting.
I guess I'd better go pack since I'm leaving for the airport in 45 minutes!