Select the rule "All sides are congruent" from the orange Select a rule box
and "All angles are congruent" from the green Select a rule box. This will draw
two overlapping ovals on your screen called a Venn diagram, creating four
regions:

- The orange region is where only the rule "All sides are congruent" applies.
Drag one shape from the shapes menu that you think belongs in this region.
- The green region is where only the rule "All angles are congruent" applies.
Drag one shape from the shapes menu that you think belongs in this region.
- The orange and green region, where the ovals overlap, is where both rules
apply. What statement can you make using mathematical language about this
region? Drag one shape from the shapes menu that you think belongs in this
region.
- The blue region is where neither rule applies. What statement can you make
using mathematical language about the blue region? Drag one shape from the
shapes menu that you think belongs in this region.

You should now have four shapes in each of the four regions of your work
area. Click the Checkmark button at the bottom to see if you've correctly placed
your shapes. If any are incorrect, try to move them to the correct region and
find a different shape that might belong in the empty region. Keep checking your
answers until all four regions have a shape.

Looking at the shapes in your work area, what do they have in common? How are
they different?

Try moving the remaining shapes into the correct region. Check your answers
as you work. When you are finished, write some true mathematical statements
about your Venn diagram, and then clear the work area and try this activity with
two other rules.