CBSE Maths eBooks CBSE Guess > eBooks > Class X > Maths Part II by Mr. M. P. Keshari Chapter 17: Coordinate Geometry We are already familiar with plotting a point on a plane graph paper. For this we take two perpendicular lines XoX’ and YoY’ intersecting at O. XOX’ is called xaxis or abscissa and YoY’ is called yaxis or ordinate. Point in a plane Let us take a point P in a plane. Let XOX’ and YOY’ be pendicualr to each other at O. are drawn. If OM = x and ON = y then xcoordinate of P is x and ycoordinate of P is y. Here we write xcoordinate first. Hence (x, y) and (y, x) are different point whenever . The two lines XOX’ and YOY’ divides the plane into four parts called quadrants. XOY, YOX’, X’OY’ and Y’OX are respectively the first second, third and and fourth quadrants. We take the direction from O to X and O to Y as positive and the direction from O to X’ and O to Y’ as negative. Distance between two points Let P (x_{1}, y_{1}) and Q (x_{2}, y_{2}) be the two points. We have to find PQ.
Section Formula Let P (x, y) divided a line AB such that AP : PB = m_{1} : m_{2}. Let coordinates of A are (x_{1}, y_{1}) and B are (x_{2}, y_{2}).
Maths by Mr. M. P. Keshari

