The x-axis and the y-axis divide the co-ordinate plane into four regions. These regions are called as Quadrants. They are shown in the following figure.
i) The upper right quadrant is the 1st quadrant. The values of x
co-ordinate and y co-ordinate of any point in this quadrant is
always positive. Its ordered pair is expressed as ( +, + ).
ii) The upper left quadrant is the 2nd quadrant. Here the
value of the x co-ordinate is negative (measured left from
the origin) but the value of the y-co-ordinate is
always positive. The ordered pair is expressed as ( -, + ).
iii) The lower left quadrant is the 3rd quadrant. The values
of the x-co-ordinate and the y-co-ordinate are both nega-
tive here. The ordered pair is expressed as (-, -).
iv) The lower right quadrant is the 4th quadrant. In
this quadrant the x-co-ordinate has a positive value and the
y-co-ordinate has a negative value. The ordered pair
is expressed as ( +, - ).