# Plotting Points

Parts of the Coordinate Plane

The coordinate plane is a way to express numbers and equations graphically.  It contains two axes, the x and the y.  The x axis is the horizontal (left and right) and the y axis is the vertical (up and down).  The center of the plane is a point called the origin.  Numbers on the x-axis count up in positive numbers to the right of the origin and down in negative numbers to the left of the origin.  Numbers on the y-axis count up in positive numbers above the origin and down in negative numbers below the origin.

Ordered Pairs

Every point on the coordinate plane is expressed as an ordered pair.  The first digit of the ordered pair is the x-coordinate.  That is how far to the left or right the point is on the x-axis.  The second number of the ordered pair is the y-coordinate.  That is how far up or down on the y-axis the point is.  All ordered pairs are written in the format (x,y).  For example, if you want to plot the point (3, 2), you would count to the right 3 spaces on the x-axis, then count up 2 spaces on the y-axis.

If the point is (-5,3) you would count to the left 5, then up 3.

Distance Formula

If you have two points that you need to find the distance between, you have a distance formula available on your formula sheet.  The distance formula is:

Designate your two points as point 1 and 2.  Then plug the x-coordinate of your first point in place of the x1, then the x-coordinate of your second point in place of the x2, then the y-coordinates in place of y1 and y2.  Then solve for d.