Interior angles in a triangle add up to 180˚. Triangles close triangleA polygon with three straight sides. have three sides, therefore they have three angles. Interior angles in a triangle sum to a ...

Learn about angles in triangles and quadrilaterals with this BBC Bitesize Maths article. For students between the ages of 11 and 14.

The Mathematical Gazette is the original journal of the Mathematical Association and it is now over a century old. Its readership is a mixture of school teachers, college and university lecturers, ...

Demetra Pitta-Pantazi, Constantinos Christou, Cognitive Styles, Dynamic Geometry and Measurement Performance, Educational Studies in Mathematics, Vol. 70, No. 1 (Jan ...