To draw a triangle with compass and ruler you need paper, a compass, a ruler and a pencil. An eraser may also be helpful.
The animation below shows step by step how to draw an equilateral triangle inscribed in a circle using a compass and ruler.
Watch how the equilateral triangle inscribed in a circle is built:
Image by Aldoaldoz, license CC BY-SA 3.0, via Wikimedia Commons.
Click on any element to learn more.