Coordinates of a Point
The positive direction on the x-axis is to the right and the positive direction on the y-axis is upward. The negative direction of x-axis is to the left and negative direction of y-axis is downwards. Each point in the plane corresponds to an ordered pair (x, y) of real numbers x and y, called co-ordinates of the point. In this figure note that (2, 1) lies in the first quadrant, (-3, 2) in the second quadrant, (-2 , 3) in the third quadrant and (3, -4) in the fourth quadrant.