**Van, a 4th grader, graphs in 3D**

**Van started making up
equations, and one was in 3 variables. When Don saw this he decided to get
Van graphing in 3D. He had done some graphing of linear functions in 2D. **

**[Theodore
Gray, co-founder of Wolfram Research, Inc
makers of Mathematica,
Popular Science columnist, element
collector, creator and builder of The
Wooden Periodic Table Table,
and author of the book The
Elements (2009), when he worked with Donas a 5th grader many
years ago, he invented a 3D graphing board- a thin plywood board with holes, with
marked wooden dowel rods, and used rubber bands to mark the points]. **

**Don took out the board and
rods so Van could use them. Don suggested he graph x+y+z=4. After figuring out
how the board worked, where the x, y and z-axes where, and how to plot a
point, he proceeded to make a table of values, then plot the graph. Van decided though, that instead of having the
points be the rubber bands, he decided to let the top
of the rod be the points plotted, which was much better because it was easier to see what the
resulting graph looked like -in this case, part of a plane. He thought he would put a piece of cloth
over the rods to show the plane better. His graph is shown from various angles
below.**

**Don also showed Van the same
graph as done in DPGraph (David Parker's very fine 3D
graphing software, and very inexpensive):**

**Fine work, Van!**

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