1. Geometry 3 Level 1

3. If you put the three angles of a triangle together they make…

4. A straight line

6. Another proof

7. Fold point C to AB. The fold should be parallel to AB.

9. Find x 62 54 x

10. Find x x 4x4x x

11. x 4x4x x

12. x 4x4x x

13. Can you read French?

14. Yes, we wanted all angles.

15. Isosceles triangle Two sides are the same i.e. AC = BC Two angles are the same

16. Name the base angles

17. Find x x

18. x = 72 Reason:

19. Here’s a hard one. Find the value of. if AB + BP = AQ +QB?

20. 1. Extend line AB to a point called R. 2. Make BR equal in length to BP. 3. Since AB+BP = AQ+QB, you can prove that AR=AC. 4. Triangle BRP is an isosceles triangle with the big angle equal to 180 degrees — 2 beta. 5. Thus, angle BRP has to equal beta. 6. If angle BRP=beta, then angle ACB also equals beta because line AP bisects angle A. 7. Therefore the two halves of the chevron formed by points A, R, P, and C are identical. 8. If angle C = beta and angle B=2 beta, then beta has to equal 40 degrees for the triangle ABC to add to 180 degrees.

21. Angles in a quadrilateral

22. Find the angles in the quadrilateral

25. Find x

26. Exterior angles

28. Exterior angle

29. Exterior angle equals the sum of the opposite interior angles.

30. Find the value of x. 70 50 x

31. Find the value of x. 70 50 x = 70 + 50 = 120