Ordered Pairs

A coordinate plane is created by a horizontal line (the x-axis) and a vertical line (the y-axis) that intersect. The point of intersection is called the origin, O. The coordinate plane can also be called a Cartesian plane.
  C and D are points on the coordinate plane.
To describe the position of any point, we use two numbers (x, y). x is called the x-coordinate and y is called the y-coordinate. x and y are called coordinates.

x tells you the horizontal position from the origin. y tells you the vertical position from the origin. (x, y) is called an ordered pair.

The coordinates of point C is (-3, -3).
The coordinates of point D is (2, 4).
The coordinates of the origin is always (0, 0).

x, y Value Point Position
positive x right of the origin
negative x left of the origin
positive y above the origin
negative y below the origin
x = 0 on the x-axis
y = 0 on the y-axis
x = 0, y = 0 O, the origin

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