Constructing trianglesConstructing a triangle using a protractor

Learn how to construct triangles using a pencil, a piece of paper, a ruler, a protractor and a compass.

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Constructing a triangle using a protractor

There are two types of triangle that you might be required to construct using a ruler and protractor. The first type is where you are given two sides and the included angle (SAS). The second type is where you are given two angles and the included side (ASA).

SAS: side - angle - side

ASA: angle - side - angle

Two sides and the included angle (SAS)

Image gallerySkip image gallerySlide1 of 5, Side-angle-side triangle, Constructing a triangle with SAS

Two angles and the included side (ASA)

Image gallerySkip image gallerySlide1 of 5, Angle-side-angle triangle, Constructing a triangle with ASA