How to Draw an Equilateral Triangle

If you don't have access to a compass or a protractor, you can use an object with a circular base to trace out an arc instead. This method is essentially the same as using a compass, but you will need to be smart about it!

1. 1
   Choose your circular object. Use almost any cylindrical object with a circular base, like a bottle or a soup can. Try using a circular roll of tape or a CD. If you are going to substitute the arc of this object for the arc of a compass tracer, you'll need to choose an object of the right size. In this method, each side of the equilateral triangle will be as long as the radius (half the diameter) of the circular object.

   • If you use a CD as your object: imagine an equilateral triangle that fits into the top-right quadrant of a CD.
   

   Complete geometry assignments with ease. "When I had homework constructing different shapes, the step-by-step pictures in this article saved me. Showing multiple techniques for making an equilateral triangle, from using compasses to stuff like water bottles or tape rolls, made the whole assignment a breeze to tackle. Big win!" - Ashley J.

   Discover foolproof methods for any classroom. "For a class experiment where we needed to build towers with equilateral triangle bases, I loved how this piece offered various approaches you could adjust to work with the random supplies available. Being able to MacGyver a solid game plan with my limited materials was so clutch!" - Cherie E.

   Gain geometric insight through experimentation. "Needing an equilateral triangle for a math project, I appreciated that they didn't just show you how to draw one but let you explore the logic behind the steps hands-on. Getting to actively test out examples myself gave me a deeper intuitive understanding of how shapes fit together. Mad helpful!" - Emily C.

   Internalize concepts through visual models. "I used to struggle picturing theoretical geometry rules until I followed this guide, constructing a test triangle step-by-step. Being able to physically walk through forming the shape brought the underlying concepts together for me. Having those interactive visuals made a world of difference in getting geometry to click!" - Mahirah M.

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2. 2
   Draw the first side. It should be exactly as long as the radius of the circular object – the distance halfway across. Make sure that it is perfectly straight!

   • If you have a ruler: simply measure the diameter of the object and draw a line that is half as long.
   • If you don't have a ruler: place the circular object onto a sheet of paper, then carefully trace the circumference with your pencil. Remove the object, and you should have a perfect circle. Use a straight edge to draw a line across the exact center of the circle: the point that is completely equidistant from any point around the circumference of the circle.
3. 3
   Use the circular object to trace an arc. Place the object over the line segment, with the edge of the circle resting at one end of the line. For accuracy, make sure that the line cleaves through the exact center of the circle. Use your pencil to trace an arc: roughly one-quarter of the way around the perimeter of the circle. ^[6]
4. 4
   Trace another arc. Now, shift the circular object so that the edge touches the other end of the line segment. Make sure that the line segment runs through the exact center of the circle. Draw another quarter-arc that crosses the first arc at a point directly above the line segment. This point is the apex of your triangle.
5. 5
   Complete the triangle. Draw the remaining sides of the triangle: two more straight lines will connect the apex with the two open ends of the line segment. Now, you should have a perfectly equilateral triangle!
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1. 1
   Draw the first side. Use a ruler or the straight edge of your protractor to trace a straight line segment of an appropriate length. This line segment will become the first side of your triangle, and each of the other sides will be just as long – so make sure that it's the right size! ^[7]
2. 2
   Use a protractor to measure a 60° angle at one end. ^[8]
3. 3
   Trace the second side. Measure out a new line segment that is equal in length to the first. Start it at one end of the original line segment, where you measured the 60° angle. Start from the vertex (the point) of the angle, and trace the straight edge of the protractor until you reach the next "point." ^[9]
4. 4
   Finish the triangle. Use the straight edge of your protractor to trace out the final side of the triangle. Connect the point at the end of the second line segment to the unattached end of the first line segment. You should now have an equilateral triangle.
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