← 4.2 Geometrical Constructions
Constructing 120 and 105 degrees
Mathematics · Grade 7 · about 40 minutes
Build 120° as the neighbour of 60° on a straight line, and 105° as 60° plus 45° at one vertex.
Sign in to read this lesson
Lessons are for learners and teachers with an account. Browsing the curriculum — subjects, strands and what each sub-strand covers — stays open to everyone.
- 7 sections of explanation, worked examples and diagrams
- 1 practice task with hints and worked answers
- A quiz that marks itself as you go
- Your progress kept across every subject you take
Other lessons in this sub-strand
- Measuring angles
- Bisecting an angle
- Constructing 60 degrees
- Constructing 90 degrees
- Constructing 30 and 45 degrees
- Constructing 120 and 105 degrees
- Multiples of 7.5 degrees
- Triangle given three sides
- Triangle given two sides and the included angle
- Triangle given two angles and a side
- Constructing a circle
- Constructions in real life