Parallel lines are a fixed distance apart and will never meet, no matter how long they are extended. Lines that are parallel have the same gradient. The graphs above, \(y = 2x + 1\) and \(y = 2x - 2\) ...
If you took Geometry in High School, you almost definitely learned it as a subject based on rules and axioms discovered by the ancient Greeks. The details of this subject, which I must admit was ...
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.
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 ...