GeoGebra Classroom

# Introduction to Rectangular Coordinates

The x-axis and y-axis are axes in the Cartesian coordinate system. Together, they form a coordinate plane. The x-axis is usually the horizontal axis, while the y-axis is the vertical axis. They are represented by two number lines that intersect perpendicularly at the origin, located at (0, 0), as shown in the figure below. To plot a point on the plane, we start at the origin and take marching orders from an ordered pair of numbers called the coordinates of the point. The x-axis comes first, and then the y-axis. For the point (1,2), the x- coordinate is 1 and the y- coordinate is 2. Use the applet below to explore this. Notice how the animation first translates from the origin horizontally and then vertically. This helps is remember that the x coordinate comes first and then the y one. Warning- when you do slopes you will need to take vertical rise first!
Notice how the animation first translates from the origin horizontally and then vertically. This helps is remember that the x coordinate comes first and then the y one. Warning- when you do slopes you will need to take vertical rise first!