Straight lines can be drawn in any direction. Horizontal lines go left and right. Vertical lines go up and down. Parallel lines are a fixed distance apart and will never meet, no matter how long they ...

Horizontal lines run left to right, parallel to the horizon, with slope 0 and equation y = k. Vertical lines run top to bottom, perpendicular to the horizon, with undefined slope and equation x = k.

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 ...