__maths__>__Construction / Practical Geometry (basics)__>__Standard angles Using Campus__### Constructing `15^@` using a compass

In this page, a short and to-the-point overview of constructing `15^@` angle using a compass is provided.

*click on the content to continue..*

Which of the following help to construct `15^@` angle using a compass?

- construct `60^@` and bisect that twice
- construct `60^@` and bisect that twice
- `15^@` angle cannot be constructed using a compass

The answer is "construct `60^@` and bisect that twice"

We have learned constructing `60^@` and bisecting an angle using a compass. Combine these two to construct `15^@` angle.

• With an arbitrary distance-measure on compass, mark point `P` from point `A` on line `bar(AB)`.

• With the same distance measure on compass, construct two arcs from points `A` and `P`. The arcs cut at point `Q`. `bar(AQ)` makes `60^@` with the `bar(AP)`.

• With an arbitrary distance-measure on compass, construct two arcs from points `P` and `Q`. These arcs cut at point `R`. The line `bar(AR)` bisects the angle `/_PAQ`.

• With an arbitrary distance-measure on compass, construct two arcs from points `P` and `R`. These arcs cut at point `S`. The line `bar(AS)` bisects the angle `/_PAS`.

The angle `15^@` is constructed as `/_PAS`.

**Constructing `15^@` angle using a Compass** : Construct an equilateral triangle and the angle `60^@` is constructed at the vertex. Bisect the angle twice.

*slide-show version coming soon*