Coordinates

2D Coordinatesvideo

2D coordinates

What is the Cartesian plane?

• The Cartesian plane is a two-dimensional grid that has

  • a horizontal scale, called the x-axis

  • a vertical scale, called the y-axis

• The two axes meet at the origin

  • where x  and y  are both 0

What are coordinates?

• Coordinates are a pair of numbers, x  and y , that describe the location of a point on the grid

  • They are written in brackets as (x , y )

  • The point is

    • x  units on the horizontal scale

    • y  units on the vertical scale

• The origin is (0, 0)

  • Positive values of x  are to the right of the origin

    • Negative values are to the left

  • Positive values of y  are above the origin

    • Negative values are below

• For example, from the origin:

  • (2, 5) is the point 2 units to the right and 5 units up

  • (-1, -4) is the point 1 unit to the left and 4 units down

• "Along the corridor, up the stairs" helps to remember horizontal then vertical, (x , y)