Lesson:
1. Remind students that Descartes was the French
mathematician who developed the coordinate system. In
fact, the rectangular coordinate system is often called
the Cartesian Coordinate System.
2. Go over homework problems. Discuss hyperbolas which
are rotated 45 degrees, such as xy = 1.
3. Explain the Tracker game.
In the TRACKER game, graphs are hidden on a coordinate grid.
Students gather clues about the location of the graphs by using
"probe shots." These probe shots are horizontal and vertical lines.
Each point where the probe crosses the hidden graphs is marked on
the screen. After using probes to locate a graph, students send a
"tracker" along the graph by entering its equation.
We will play the Novice Game.
In the Novice Game, you choose two types of graphs to be hidden on the grid.
There are always three hidden graphs: two of one type and one of the other.
One type of graph is marked with X's and the other with O's when crossed by
a probe shot. If a hidden graph is a hyperbola, it could be of either kind
and not necessarily the same kind as another hidden hyperbola.
The game ends when you have found all the hidden graphs. When you finish a
game with a positive score, the program compares your game score to those
in the TRACKER Novice Game section of your Records file. If your score is
higher than the lowest score currently in the Novice Game section, or the
Novice Game section has fewer than ten scores saved in it, you will be
offered the opportunity to add your game to the Records. A game added to
the Records will be erased when it is no longer in the top ten scores for
that game.
4. Distribute copies of the Worksheet #1 and Worksheet #2.
Explain the scoring of the game.
Worksheet #1
Worksheet #2
5. Have students play "Tracker" on the computer using
ellipses, hyperbolas, parabolas, circles, and lines.
6. Students should record the results of their games on
Worksheet #2.