Axiom : If a line does not lie in a plane but intersects it, their intersection is a point (figure 1.7 ).

Figure 1.6

Point A is the intersection point of line l and plane P.

Take any three non-collinear points A,B and C on a paper. How many different lines can be drawn through different pairs of points ? Name the lines.

Three lines can drawn namely AB, BC & AC.

Example 2

Figure 1.7

From figure 1.7 answer the following :

1. Name lines parallel to line AB

2. Are line AO and point R coplanar ? Why ?

3. Are points A, S, B and R coplanar ? Why ?

4. Name three planes passing through at A.

1. Line CD, line SR and line PQ.

2. Yes. Any line and a point outside it are coplanar.

3. Yes. Two parallel line are always coplanar.

4. ABCD , ADSP and ADCB.

Index

Introduction

1.1 Points, Lines and Planes
1.2 Line Segment
1.3 Rays and Angles
1.4 Some Special Angles
1.5 Angles made by a Transversal
1.6 Transversal Across Two Parallel Lines
1.7 Conditions for Parallelism

Chapter 2