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.

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 ...

A horizontal line on a distance-time graph close distance-time graphA graph with distance travelled plotted on the vertical axis against time taken on the horizontal axis. shows that the object is ...