1. Perpendicular bisector of a line.
Join up the points where your circles cross.
Draw a circle with centre A.
Draw the same size circle with centre B A B
Perpendicular Bisector

2. Draw an arc with the point as the centre.
Perpendicular from a point to a line.
Draw an arc with the point as the centre.

3. Draw circles with centres on the two arcs.
Perpendicular from a point to a line.
Draw circles with centres on the two arcs.
Perpendicular line

4. Draw arcs from the point that cut the line.
Perpendicular from a point on a line.
Draw arcs from the point that cut the line.

5. Draw circles with centres on the two arcs.
Perpendicular from a point on a line.
Draw circles with centres on the two arcs.

6. Draw arcs from the angle to cut the lines
Angle Bisector.
Draw arcs from the angle to cut the lines

7. Draw circles with centres on the two arcs.
Angle Bisector.
Draw circles with centres on the two arcs.

8. Has the line bisected the angle?
Angle Bisector.
Has the line bisected the angle?

9. From this point draw a circle (arc) of the same radius
From the starting point draw a circle of any radius.

10. Join the intersection to your starting point.
Measure your angle

11. 90 degree angle.
From this point draw a circle (arc) of the same radius
Start with the 600 angle (but don’t join it up)

12. 90 degree angle. Join up the intersections
From these arcs draw two more intersecting circles
You now have a right angle!