## Precalculus (6th Edition) Blitzer

In the rectangular system of coordinates, an ordered pair is $\left( x,y \right)$, where the number written on the left is the x coordinate and the one written on the right is the y coordinate. When the x coordinate is positive, it will be plotted on the right side of the vertical axis and when it is negative, it will be plotted on the left. Similarly, if the y coordinate is positive, it will be plotted above the horizontal axis and when it is negative, it will be plotted below it.