For this topic you will need a ruler, a protractor, a set square and a pair of compasses. It is best to own your own personal equipment, then you become familiar with using it well and don’t get any last minute surprises such as finding the compass arms are too loose.

Drawing triangles knowing ASA

If we know two angles of a triangle and the side length between them, we can draw the side length and then measure the angle from each end of that side. If we extend the lines at each of these angles, they will join to make the appropriate triangle.

Exercise 1 (needs ruler and protractor)

Using a pair of compasses

Many triangles can only be drawn using a pair of compasses, for instance if we know SSS.

To get used to using a pair of compasses we will start by just drawing lines with them, then practice more advanced constructions.

Exercise 2 (needs ruler, protractor and pair of compasses)

Set Squares

If we need to draw perpendicular lines, a set square is often more convenient than a protractor. Let’s practice using them.

We can also use a set square in conjunction with a ruler to draw a pair of parallel lines that are a fixed distance apart.

Exercise 3

Answers to all three exercises

Below are the answers to those parts of the questions that have specific answers: