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.

When you create a graph in Excel, the software automatically sizes the X and Y axis lines, so the data you want to display is shown. You can override the settings and set the vertical and horizontal ...

Whether you are sketching graphs in mathematics, understanding directions in geography, or reading blueprints in design class, horizontal and vertical lines are concepts you cannot avoid. They form ...