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The figure shows a rectangle PRSU with a line QT, which divides the rectangle into two squares.

How many right-angle triangles can be drawn using any three points P, Q, R, S, T, U as corners?

If you liked this problem, here is an NRICH task which challenges you to use similar mathematical ideas.

*This problem is taken from the UKMT Mathematical Challenges.**View the archive of all weekly problems grouped by curriculum topic*