__maths__>__Construction / Practical Geometry (basics)__>__Construction of Triangles (Fundamental Shape of Polygons)__### Construction of Triangle(SAS)

In this page, a short and to-the-point overview of constructing triangles with side-angle-side (angle between given two sides) is provided.

*click on the content to continue..*

To construct a triangle, "side-angle-side" is provided. Which of the following is required to construct the specified triangle?

- a scale and a compass to mark the given sides
- a protractor, compass and scale to mark angles and sides
- a protractor, compass and scale to mark angles and sides
- a set-square and protractor to mark parallel lines and angle

The answer is "a protractor and compass+scale to mark angles and sides"

To construct a triangle `/_\ ABC` with given "side-angle-side" `4`cm, `70^@`, and `6`cm. • Construct a line and mark side `bar(AB)` with a compass measuring `6`cm

• measure `70^@` angle and draw a ray from point `A`

• measure `bar(AC)` `4`cm in a compass and draw an arc cutting the ray

• the arc and the ray cut at point `C`. Connect the point to point `B` to get `bar(BC)`

`/_\ ABC` is constructed.

**Construction of SAS triangle** : use compass to the measure lengths and protractor to measure the given angle. Once the vertices are marked, join them to form the triangle.

*slide-show version coming soon*