1. Form 1 Mathematics Chapter 6

2.  Lesson requirement  Textbook 1A  Workbook 1A  Notebook (and folder)  Before lessons start  Desks in good order!  No rubbish around!

3.  Geo-: land, earth (shape)  -metry: metre (measure)  Basic concepts of Geometry  Points 點  Lines 線  Planes 面  (Solids) 體

4.  Points 點  Lines 線  Planes 面

5.  When two lines intersect each other, they also form an angle between them.  The two lines are called the arms ( 射線 ) of the angle.  The point where the arms meet is called the vertex ( 頂點 ) of the angle.

6.  Name of angles  The middle letter “B” is the vertex!

7.  There are six types:

8.  Note: Any two line segments that meet each other form two angles.  We name  x as “  DAC”, and we name  y as “the reflex angle  DAC”.

9.  Name the angles below:

10.  When two lines in the same plane, but they do not intersect each other, they are called parallel lines ( 平行線 )  A pair of parallel lines is denoted by a pair of arrows ( 箭號 )  We write “AB // CD”

11.  When two lines in the same plane are intersecting at right angle (90  ), they are called perpendicular lines ( 垂直線 )  A right angle will be clearly shown in a pair of perpendicular lines  We write “AB  CD”

12.  Pages 233 – 234 of Textbook 1A  Questions 1 – 9  Pages 107 – 110 of Workbook 1A  Questions 1 – 8

13.  OBQ Re-Correction  Today!  CBQ Correction  23 Jan (Wed)  SHW (I)  23 Jan (Wed)

14. Enjoy the world of Mathematics! Ronald HUI