Draw a square. A second square of the same size slides around the
first always maintaining contact and keeping the same orientation.
How far does the dot travel?
Age 11 to 14 Challenge Level
How does the area of the triangle compare to the area of the parallelogram? How do you know? How can you use this to create a formula for the area of a triangle in terms of the area of a parallelogram?
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.