# Triangle calculator

Please enter what you know about the triangle:
You have entered side a, b and c.

### Obtuse scalene triangle.

Sides: a = 40   b = 60   c = 80

Area: T = 1161.895500386
Perimeter: p = 180
Semiperimeter: s = 90

Angle ∠ A = α = 28.95550243719° = 28°57'18″ = 0.50553605103 rad
Angle ∠ B = β = 46.56774634422° = 46°34'3″ = 0.81327555614 rad
Angle ∠ C = γ = 104.4787512186° = 104°28'39″ = 1.82334765819 rad

Height: ha = 58.09547501931
Height: hb = 38.73298334621
Height: hc = 29.04773750966

Median: ma = 67.82332998313
Median: mb = 55.67876436283
Median: mc = 31.62327766017

Inradius: r = 12.91099444874
Circumradius: R = 41.31218223595

Vertex coordinates: A[80; 0] B[0; 0] C[27.5; 29.04773750966]
Centroid: CG[35.83333333333; 9.68224583655]
Coordinates of the circumscribed circle: U[40; -10.32879555899]
Coordinates of the inscribed circle: I[30; 12.91099444874]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 151.0454975628° = 151°2'42″ = 0.50553605103 rad
∠ B' = β' = 133.4332536558° = 133°25'57″ = 0.81327555614 rad
∠ C' = γ' = 75.52224878141° = 75°31'21″ = 1.82334765819 rad

# How did we calculate this triangle?

### 1. Input data entered: side a, b and c. ### 2. The triangle circumference is the sum of the lengths of its three sides ### 3. Semiperimeter of the triangle ### 4. The triangle area using Heron's formula ### 5. Calculate the heights of the triangle from its area. ### 6. Calculation of the inner angles of the triangle using a Law of Cosines ### 7. Inradius ### 8. Circumradius ### 9. 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.