Stage: 4 and 5 Challenge Level: 
Make cards from the images in this document .
Do they help you to make connections?
Can you arrange them in ways that help you to see some of the properties of the problem image?
epsilons. Isosceles triangles. Radius (radii) & diameters. Long problems. Cosine rule. Maximise/minimise/optimise. Working systematically. Factors and multiples. Pythagoras' theorem. smartphone.
Published April 1998,October 2008.
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