Cartesian Coordinate and Identifying Ordered Pairs - Middle School

Identify the three pairs of points (A) (B) and (C) plotted on the following graph?

Answer:

Point (A) = (3, 0)
Point (B) = (0 , -2)
Point (C) = (-3 , -4)

Explanation:

The graph represents what is termed as the rectangular or Cartesian coordinate system. This system is constructed by drawing two perpendicular lines. The horizontal one is called the x-axis. The vertical is called the y-axis. The point were the two lines cross is called the origin which is represented as (0,0). These axes divide the plane into four quadrants numbered I to IV in a counter- clockwise direction. An ordered pair is always written in the form (x,y) where the x coordinate appears first and then the y.

Working from right to left, the first pair of points (A) is located in quadrant I. This pair of points is located on the x-axis. In this case the y will be 0. Since the x coordinate appears to the right of the origin then it is positive. Therefore, this pair is (3,0).

The second pair of points (B) is located on the y-axis. In this case x will be 0. Since the y coordinate appears below the origin then it is negative. Therefore this pair is (0, -2).

The Third pair of points (C) is located in quadrant III. In this quadrant both the x and y coordinates are negative. To find out what the pair is, start at the origin and count 3 spaces to the left and 4 spaces down. The intersection is the point (-3, -4).

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