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.

Graphs are often used in everyday life to give information about how two quantities are related. A conversion graph is a straight-line graph that shows the relationship between two units of ...

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 ...