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Isosceles

Age 11 to 14
Challenge Level Yellow starYellow starYellow star
Secondary curriculum
  • Problem
  • Student Solutions

Prove that a triangle with sides of length 5, 5 and 6 has the same area as a triangle with sides of length 5, 5 and 8.

Find other pairs of isosceles triangles which are not congruent but have equal areas.

How many isosceles triangles have an area of 12 square units?


 

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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.

NRICH is part of the family of activities in the Millennium Mathematics Project.

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