The first number ( x) specifies how far along the x (horizontal) axis the point is. The two numbers in parentheses are the x and y coordinate of the point.

The letter P is simply the name of the point and is used to distinguish it from others. The coordinates are written as an 'ordered pair'. It is conventional to label them with numerals but we talk about them as 'first, second, third, and fourth quadrant'. In the diagram above they are labeled Quadrant 1, 2 etc. The first quadrant, by convention, is the top right, and then they go around counter-clockwise. When the origin is in the center of the plane, they divide it into four areas called quadrants. The point where the two axes cross (at zero on both scales) is called the origin. Values above the origin are positive and those below are negative. The vertical scale is called the y-axis and is also usually drawn with the zero point in the middle. Values to the right are positive and those to the left are negative. The horizontal scale is called the x-axis and is usually drawn with the zero point in the middle. These are the coordinates of the point A, sometimes referred to as its 'rectangular coordinates'. So in the diagram above, the point A has an x value of 20 and a y value of 15. Together, they define a single, unique position on the plane. The plural of axis is 'axes' (pronounced 'AXE-ease').ДЄ point's location on the plane is given by two numbers, one that tells where it is on the x-axis and another which tells where it is on the y-axis. It has two scales, called the x-axis and y-axis, at right angles to each other. The coordinate plane is a two-dimensional surface on which we can plot points, lines and curves. In coordinate geometry, points are placed on the 'coordinate plane' as shown below. Get The Official GMAT Club's App - GMAT TOOLKIT 2.Д¬oordinate geometry, or Cartesian geometry, is the study of geometry using a coordinate system and the principles of algebra and analysis.

Coordinate geometry