We’ve all learned “parallel lines never intersect” in high school geometry. But what your teachers failed to explain is that “parallel lines never intersect” is only true in Euclidean geometry, which ...

Revise the different types of angles and rules for calculating angles. This guide includes interactive activities and a quiz. NEW: Angles in parallel lines Revise alternate, correspondent or ...

Many a mathematician has received a long letter from an unknown sender who claims to have found a way to trisect an angle using only a straightedge and compass. The mathematician may read passages of ...