Co-ordinate Geometry(Triangles-Straight lines)
Co-ordinate Geometry (Triangles-Straight lines) Co-ordinate Geometry is also called Analytical Geometry. It is the branch of Geometry in which we use two numbers, called Co-ordinates to indicate the position of a point in a plane. Any point in a plane can be located in position with reference to two mutually perpendicular lines called "Co-ordinate Axes" or simple "axes". The horizontal reference line is called the x-axis, and the vertical reference line is called the y-axis. As Shown in the below figure , XX' is the x-axis and YY' is the y-axis. The point of intersection of these two axes is called origin. Let P be any point in the plane. From P draw PM perpendicular to OX. Then the lengths of OM and MP are called the co-ordinates of P(usually denoted by x and y respectively). The length of OM is called the x co-ordinate or the abcissa and the length PM is called the y co-ordinate or ordinate of P. Hence a point P can be denoted as ...