At a Glance

The area of a regular pentagon looks about twice as a big as the pentangle star drawn within it. Is it?

Darts and Kites

Explore the geometry of these dart and kite shapes!

No Right Angle Here

Prove that the internal angle bisectors of a triangle will never be perpendicular to each other.

Angles in Three Squares

Age 11 to 16 Challenge Level:

In the diagram below, can you find angles equal to $a, b$ and $c$ from the problem?

What is special about triangle ABC?