Stage: 3 Challenge Level: 
Draw all the possible distinct triangles on a 4 x 4 dotty grid.
N.B. Distinct triangles cannot be placed one over the other by translating, rotating or reflecting them.
Convince me that you have all possible triangles.
Generalising. Interactivities. Cubes. Mixed triangles. Squares. Mathematical reasoning & proof. Visualising. Congruence. Working systematically. Compound transformations.
Published November 2002,December 2002.
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