Prove that the internal angle bisectors of a triangle will never be
perpendicular to each other.
Angles in Three Squares
Age 14 to 16 Challenge Level
The picture below shows three squares.
Surprisingly, $c = a + b$.
Can you prove it?
Once you've had a chance to think about how to prove it, click to reveal the diagram below.
Can you use the diagram to help you construct a proof?
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.