### Theory

 1 Introduction 2 Basic proportionality or Thales theorem 3 Angle bisector theorem and its converse 4 Types of construction of triangle 5 Construction of a triangle when its base, vertical angle and median are given 6 Construction of a triangle when its base, vertical angle and altitude are given 7 Construction of a triangle if its base, vertical angle and the point on the base are given

### Exercises

 1 Calculate the side AD of triangle ABC Difficulty: easy 1 2 Determine the side CB of triangle ABC Difficulty: easy 3 3 Calculate the value of the variable Difficulty: easy 3 4 Find the length of AE of triangle ABC Difficulty: easy 3 5 Determine the value of the variable Difficulty: medium 4 6 Find the side length of the triangle Difficulty: medium 4 7 Check whether the lines of the triangle are parallel Difficulty: medium 4 8 Determine the length of PM Difficulty: medium 4 9 Calculate the length of PT and VQ Difficulty: medium 4 10 Check whether CD is the bisector of angle C Difficulty: medium 4 11 Observe the picture and answer the questions Difficulty: hard 6 12 Determine the height of the small tree Difficulty: hard 5 13 Calculate the height of the mother Difficulty: hard 5 14 Verify the trees are parallel Difficulty: hard 5 15 Prove the theorem Difficulty: hard 5

### Tests

 1 Training test I Difficulty: easy 9 2 Training test II Difficulty: medium 11 3 Training test III Difficulty: hard 12

### Teacher manual

 1 Methodical recommendation