Opportunities don’t happen, you create them. – **Chris Grosser**

# Lecture - 1 Chapter 7 Coordinate Geometry

00:00:20 Meaning and use of Coordinate Geometry

00:04:00 Derivation of Distance Formula (Finding distance between two points)

00:16:40 NCERT Exercise 7.1 Questions 1 Find the distance between the following pairs of points : (i) (2, 3), (4, 1) (ii) (– 5, 7), (– 1, 3) (iii) (*a*, *b*), (– *a*, – *b*)

00:22:00 NCERT Exercise 7.1 Questions 2 Find the distance between the points (0, 0) and (36, 15). Can you now find the distance between the two towns A and B discussed in Section 7.2.

00:24:50 NCERT Exercise 7.1 Questions 3 (Collinear points using Distance formula) Determine if the points (1, 5), (2, 3) and (– 2, – 11) are collinear.

00:34:50 NCERT Exercise 7.1 Questions 4 Check whether (5, – 2), (6, 4) and (7, – 2) are the vertices of an isosceles triangle.

00:40:00 NCERT Exercise 7.1 Questions 5 In a classroom, 4 friends are seated at the points A, B, C and D as shown in Fig. 7.8. Champa and Chameli walk into the class and after observing for a few minutes Champa asks Chameli, “Don’t you think ABCD is a square?” Chameli disagrees. Using distance formula, find which of them is correct.