Two lines in a coordinate plane are parallel if they have the same slope. The slope of a line is calculated by taking the difference in the y-coordinates and dividing by the difference in the x-coordinates. Additionally, any two vertical lines are always parallel since vertical lines have undefined slopes.

1. Terms of Endearment Parallel Lines in the Coordinate Plane: 3.6

2. Slope Rise/Run Difference in y-coordinates over the difference in x-coordinates

3. Parallel Line Slopes In a coordinate plane, two non-vertical lines are parallel if and only if they have the same slope Any two vertical lines are parallel