Everyone learns the number one rule about triangles in high school: the angles of a triangle add up to 180 degrees. But did you know that sometimes they don't? Triangles are much more interesting than ...

A race! Oh, don't forget to stretch guys. Parallel lines always stay the same distance apart, so they will never cross, no matter how long they go on for. And that's why they're used in races. Ready ...

Parallel lines close parallel lines Lines which never meet and stay the same distance apart. Parallel lines are indicated by a pair of arrows. are two or more straight lines that remain the same ...