Construct an equilateral triangle ABC with side 6 cm. Draw a circle circumscribing the triangle ABC.

Steps of construction :

1. Draw a line segment BC = 6 cm.

2. With B as center and radius 6 cm draw an arc.

3. With C as center and radius 6 cm draw another arc which intersects first arc at A.

4. Join AB and AC. ABC is the required triangle.

5. Draw perpendicular bisectors of AC, AB and BC intersecting each other at O.

6. With O as center and radius OA or OB or OC draw a circle which will pass through A, B or C.

Hence, above is the required circumcircle of triangle.