How to Draw an Equilateral Triangle Without a Compass

If you do not have a compass, you can construct an equilateral triangle with a ruler.
••• NA/ Images

An equilateral triangle has three congruent sides and three congruent angles, each measuring 60 degrees. Mathematicians usually construct them inside a circle, which they draw with a compass. However, if you do not have a compass, you can draw the triangle without using the circle guide by measuring each side carefully with a ruler. Because each angle is related to the length of the sides as described by the Law of Cosines, when all the sides are equal, all the angles will also be equal.

    Draw the base using a ruler. Take note of the exact length of the line.

    Divide the length by two. This gives you the distance to the line's midpoint.

    Draw a line perpendicular to the base at the midpoint. This is called the perpendicular bisector.

    Align the zero mark on the ruler with one end of the base.

    Rotate the ruler until the mark representing the length of the base line touches the perpendicular bisector. If it cannot touch, extend the bisector.

    Draw the line, then repeat this process to draw the third line. You now have a triangle with three congruent sides and three congruent angles, or an equilateral triangle.

Related Articles

How to Use a Protractor to Measure a Triangle
How to Find The Area of a Pentagon
How to Split a Triangle Into Fourths
Facts About Parallelograms
What Are Coterminal Angles?
How to Find the Radius of an Arc
How to Put Base Log on Graphing Calculator
How to Calculate Chord Length
How to Measure an Angle With a Ruler
How to Find Measure of a Angle
How to Use Trigonometry in Carpentry
How to Create a Justice Scale
How to Divide a Circle Into Equal Segments
How to Measure an Angle Without a Protractor
How to Calculate Sides of a Triangle
How to Build a Ferris Wheel as a School Project
How to Find the Circumference of an Octagon
How to Measure an Angle Using a Protractor
How to Find the Surface Area of Triangles
How to Draw Geometric Shapes