Equilateral triangle calculator

An equilateral triangle is a triangle where all three sides have the same length, and all three angles are also congruent and measure 60 degrees each.

If you know the length of one side of an equilateral triangle (a), you can use that information to find the perimeter (p) of the triangle: p = 3a

You can also use the side length to find the area of the triangle using the formula:

Area = (√3/4) * a²

You can also use the side length to find the height (h) or the inradius (r) of the triangle:

h = (a√3)/2
r = a/(2√3)

If you know the area of an equilateral triangle, you can use that information to find the length of one side (a) using this formula:
Area = (√3/4) * a²

You can also use the area to find the height (h) or inradius (r) of the triangle:

h = (2 * √(3 * area))/a
r = √((2 * area)/√3)

If you know the height (h) of an equilateral triangle, you can use that information to find the length of one side (a) using this formula:

a = (2 * h)/√3

Calculate an equilateral triangle by:

• side a
• area S
• height h

An equilateral triangle in word problems in mathematics:

• Triangular numbers
  The first four triangular numbers are 1,3,6,10. What is the 10th triangular number? Help: A triangular number or triangle number counts objects arranged in an equilateral triangle.
• Equilateral triangle v2
  Calculate the side of an equilateral triangle if its perimeter is 132 cm.
• Triangle
  Can an equilateral triangle have a right angle?
• The perimeter 12
  The perimeter of an equilateral triangle is 41.46 inches. If the length of each side is (q - 5.7), what is the value of q?
• Calculate
  Calculate the length of a side of the equilateral triangle with an area of 50cm².
• The coordinates 3
  The coordinates of two vertices of an equilateral triangle are (1,1) and (5,1). What are the coordinates of the third vertex?
• Trisection of a line segment
  Divide the line segment AB into three equal parts. Instructions: Construct an equilateral triangle ABC and find its center (e.g., the described circles).

• ET inscribed circle
  An equilateral triangle has been inscribed in a circle with a radius of 4 cm . Find the area of the shaded region.
• N points on the side
  An equilateral triangle A, B, and C on each of its inner sides lies N=13 points. Find the number of all triangles whose vertices lie at given points on different sides.
• Equilateral triangle
  Find the area of an equilateral triangle with a side of 15 cm.
• Funnel
  The funnel has the shape of an equilateral cone. Calculate the surface wetted with water if we poured into the funnel 7.1 liters of water.
• Equilateral cone
  The axial section of the cone is an equilateral triangle with a side of 12 cm. Surface and volume calculation.
• Equilateral 80573
  The field has the shape of an equilateral triangle. Calculate its area if you know that the side is 280 meters long.
• Equilateral 81770
  Calculate the area of the circle in which the hole is cut in the shape of an equilateral triangle when the diameter of the circle, d=32mm, and the side of the triangle, a=20.8mm.
• An equilateral triangle
  The perimeter of an equilateral triangle is 33cm. How long is each side?

more triangle problems »

Look also at our friend's collection of math problems and questions:

• Equilateral triangle
• triangle
• right triangle
• Heron's formula
• The Law of Sines
• The Law of Cosines
• Pythagorean theorem
• triangle inequality
• similarity of triangles
• The right triangle altitude theorem

See triangle basics on Wikipedia or more details on solving triangles.