So, you need to be very careful which scale you use when measuring the angles. With a protractor, the angles of any shape can found where two lines meet and form a corner.

The only tools you need to make these shapes are a straight ruler and a compass or dividers (Figure 1). It is also useful to have a protractor (to measure angles) and a drafting square (to make square ...

So, you need to be very careful which scale you use when measuring the angles. With a protractor, the angles of any shape can found where two lines meet and form a corner.