Hello, I'm Mr Firth, and together we're going to learn about lines of symmetry. Symmetry is when one side of a shape looks exactly like the other—just flipped. Lots of buildings use symmetry because ...

In general usage, symmetry most often refers to mirror or reflective symmetry; that is, a line (in 2-D) or plane (in 3-D) can be drawn through an object such that the two halves are mirror images of ...