Equilateral triangle calculator

Please enter one property of the equilateral triangle

Use symbols: a, h, T, p, r, R


You have entered side a, b and c (as equilateral triangle).

Equilateral triangle.

Sides: a = 23792379   b = 23792379   c = 23792379

Area: T = 2.45118660495E+14
Perimeter: p = 71377137
Semiperimeter: s = 35688568.5

Angle ∠ A = α = 60° = 1.04771975512 rad
Angle ∠ B = β = 60° = 1.04771975512 rad
Angle ∠ C = γ = 60° = 1.04771975512 rad

Height: ha = 20604804.63305
Height: hb = 20604804.63305
Height: hc = 20604804.63305

Median: ma = 20604804.63305
Median: mb = 20604804.63305
Median: mc = 20604804.63305

Inradius: r = 6868268.211016
Circumradius: R = 13736536.42203

Vertex coordinates: A[23792379; 0] B[0; 0] C[11896189.5; 20604804.63305]
Centroid: CG[11896189.5; 6868268.211016]
Coordinates of the circumscribed circle: U[11896189.5; 6868268.211016]
Coordinates of the inscribed circle: I[11896189.5; 6868268.211016]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 120° = 1.04771975512 rad
∠ B' = β' = 120° = 1.04771975512 rad
∠ C' = γ' = 120° = 1.04771975512 rad

Calculate another triangle




How did we calculate this triangle?

1. Input data entered: side a b c (as equilateral triangle)

a = 23792379 ; ; b = 23792379 ; ; c = 23792379 ; ;

2. From we calculate b,c:

b = c = a = 23792379 ; ;


Now we know the lengths of all three sides of the triangle and the triangle is uniquely determined. Next we calculate another its characteristics - same procedure as calculation of the triangle from the known three sides SSS.

a = 23792379 ; ; b = 23792379 ; ; c = 23792379 ; ; : Nr. 1

3. The triangle circumference is the sum of the lengths of its three sides

p = a+b+c = 23792379+23792379+23792379 = 71377137 ; ;

4. Semiperimeter of the triangle

s = fraction{ o }{ 2 } = fraction{ 71377137 }{ 2 } = 35688568.5 ; ;

5. The triangle area using Heron's formula

T = sqrt{ s(s-a)(s-b)(s-c) } ; ; T = sqrt{ 35688568.5 * (35688568.5-23792379)(35688568.5-23792379)(35688568.5-23792379) } ; ; T = sqrt{ 6.008 * 10**{ 28 } } = 2.451 * 10**{ 14 } ; ;

6. Calculate the heights of the triangle from its area.

T = fraction{ a h _a }{ 2 } ; ; h _a = fraction{ 2 T }{ a } = fraction{ 2 * 2.451 * 10**{ 14 } }{ 23792379 } = 20604804.63 ; ; h _b = fraction{ 2 T }{ b } = fraction{ 2 * 2.451 * 10**{ 14 } }{ 23792379 } = 20604804.63 ; ; h _c = fraction{ 2 T }{ c } = fraction{ 2 * 2.451 * 10**{ 14 } }{ 23792379 } = 20604804.63 ; ;

7. Calculation of the inner angles of the triangle using a Law of Cosines

a**2 = b**2+c**2 - 2bc cos( alpha ) ; ; alpha = arccos( fraction{ a**2-b**2-c**2 }{ 2bc } ) = arccos( fraction{ 23792379**2-23792379**2-23792379**2 }{ 2 * 23792379 * 23792379 } ) = 60° ; ; beta = arccos( fraction{ b**2-a**2-c**2 }{ 2ac } ) = arccos( fraction{ 23792379**2-23792379**2-23792379**2 }{ 2 * 23792379 * 23792379 } ) = 60° ; ; gamma = arccos( fraction{ c**2-a**2-b**2 }{ 2ba } ) = arccos( fraction{ 23792379**2-23792379**2-23792379**2 }{ 2 * 23792379 * 23792379 } ) = 60° ; ;

8. Inradius

T = rs ; ; r = fraction{ T }{ s } = fraction{ 2.451 * 10**{ 14 } }{ 35688568.5 } = 6868268.21 ; ;

9. Circumradius

R = fraction{ a }{ 2 * sin( alpha ) } = fraction{ 23792379 }{ 2 * sin 60° } = 13736536.42 ; ;




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

See more informations about triangles or more information about solving triangles.