# 3.5 3.5 3.5 triangle

### Equilateral triangle.

Sides: a = 3.5   b = 3.5   c = 3.5

Area: T = 5.30444055982
Perimeter: p = 10.5
Semiperimeter: s = 5.25

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

Height: ha = 3.03110889132
Height: hb = 3.03110889132
Height: hc = 3.03110889132

Median: ma = 3.03110889132
Median: mb = 3.03110889132
Median: mc = 3.03110889132

Inradius: r = 1.01103629711
Circumradius: R = 2.02107259422

Vertex coordinates: A[3.5; 0] B[0; 0] C[1.75; 3.03110889132]
Centroid: CG[1.75; 1.01103629711]
Coordinates of the circumscribed circle: U[1.75; 1.01103629711]
Coordinates of the inscribed circle: I[1.75; 1.01103629711]

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

# How did we calculate this triangle?

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. ### 1. The triangle circumference is the sum of the lengths of its three sides ### 2. Semiperimeter of the triangle ### 3. The triangle area using Heron's formula ### 4. Calculate the heights of the triangle from its area. ### 5. Calculation of the inner angles of the triangle using a Law of Cosines ### 6. Inradius ### 7. Circumradius ### 8. Calculation of medians #### Look also our friend's collection of math examples and problems:

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