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Triangular Intersection

Age 14 to 16 Short Challenge Level:


The triangle and the quadrilateral in the diagram below have 4 intersection points.

What is the largest number of intersection points that a triangle and a quadrilateral can have?


This problem is adapted from the World Mathematics Championships
You can find more short problems, arranged by curriculum topic, in our short problems collection.
The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice.
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