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Constructing an equilateral triangle

This is the step-by-step, printable version. If you PRINT this page, any ads will not be printed.

See also the animated version.

After doing this Your work should look like this
Start with the line segment AB which is the length of the sides of the desired equilateral triangle. Geometry construction with compass and straightedge or ruler or ruler
1.  Pick a point P that will be one vertex of the finished triangle. Geometry construction with compass and straightedge or ruler or ruler
2.  Place the point of the compasses on the point A and set its drawing end to point B. The compasses are now set to the length of the sides of the finished triangle. Do not change it from now on. Geometry construction with compass and straightedge or ruler or ruler
3.  With the compasses' point on P, make two arcs, each roughly where the other two vertices of the triangle will be. Geometry construction with compass and straightedge or ruler or ruler
4.  On one of the arcs, mark a point Q that will be a second vertex of the triangle. It does not matter which arc you pick, or where on the arc you draw the point. Geometry construction with compass and straightedge or ruler or ruler
5.  Place the compasses' point on Q and draw an arc that crosses the other arc, creating point R. Geometry construction with compass and straightedge or ruler or ruler
6.  Using the straightedge, draw three lines linking the points P,Q and R. Geometry construction with compass and straightedge or ruler or ruler
7.  Done. The triangle PQR is an equilateral triangle. Its side length is equal to the distance AB. Geometry construction with compass and straightedge or ruler or ruler

Other constructions pages on this site

Lines

Angles

Triangles

Right triangles

Triangle Centers

Circles, Arcs and Ellipses

Polygons

Non-Euclidean constructions