This document provides definitions and properties related to angles. It discusses interior angles that add up to (n-2)x180 in a polygon with n sides. Exterior angles add up to 360. Vertically opposite angles and corresponding angles in parallel lines are equal. Angles subtended by a semicircle are right angles of 90 degrees. Angles from the same point to the middle of a circle are twice those at the circumference. Angles in the same segment of a circle are equal.

1. Angles revision….

2. What is significant about the letters F, Z, C and U in this topic? Write down the answer in your books, with an illustration if possible. What about x? Angles

3. Interior angles These are angles inside a polygon. They add up to (n-2) x 180 where n is the number of sides Interior angles What do these angles add up to?

4. Exterior angles Add up to 360

5. Angles on a straight line Angles to a point

6. Vertically opposite angles

7. Parallel Lines a 77 a = 77 because a and 77 make an F.

8. Parallel Lines a 77 a = 77 because a and 77 make an F. “ F” angles are called corresponding angles

9. Parallel Lines a 77 a = 77 because a and 77 make a Z

10. Parallel Lines a 77 a = 77 because a and 77 make a Z. “ Z” angles are called alternate angles

11. p.18 Ex2A Q1, 10 – 15 p.19 Ex2B Q1, 4, 11, 12 p.20 Q13-15 p.21/ 22 Ex2C Q1, 6, 7, 12, 13, 14, 16-20 p.24/ 25 Ex2D Q1, 4, 10, 14, 16 p.28 Ex2E Odd Questions p.30 Ex2F Even Questions p.32 Ex2G – All questions

12. Circles chord Centre of circle to a Chord – meets at Right angles

13. tangent Radius to a tangent – meets at right angles

14. Cyclic quadrilaterals – Opposite angles add up to 180

15. An angle subtended by a semi Circle is a right angle 90

16. Angles from the same point to the middle are twice those at the circumference x 2x

17. Angles in the same segment are equal x x