Age 11 to 14
If three adjacent angles add up to 360 degrees, what do the other
three angles add up to?
The shape given in the problem does tessellate. Call the unmarked
angles D, E and F and label the angles of the polygons accordingly
in the tessellation. What do you notice?
Draw some different hexagons that satisfy the criteria and see what
happens. It may be best to work on square and/or isometric dotty
paper so that the angles can be worked out accurately and the
tessellations drawn easily.