Learn the difference between lines with the same slope and those with an opposite reciprocal slope. This quick guide breaks ...

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.

Higher - The gradients of two perpendicular lines will always multiply to make –1. Make sure you are familiar with finding the equation of a line and calculating gradient to understand equations of ...