# 10 26 28 triangle

### Obtuse scalene triangle.

Sides: a = 10   b = 26   c = 28

Area: T = 129.9854614474
Perimeter: p = 64
Semiperimeter: s = 32

Angle ∠ A = α = 20.92222396826° = 20°55'20″ = 0.36551619694 rad
Angle ∠ B = β = 68.19662520106° = 68°11'47″ = 1.19902491351 rad
Angle ∠ C = γ = 90.88215083068° = 90°52'53″ = 1.58661815491 rad

Height: ha = 25.99769228948
Height: hb = 9.9998816498
Height: hc = 9.28546153196

Median: ma = 26.55218360947
Median: mb = 16.52327116419
Median: mc = 13.85664064606

Inradius: r = 4.06220192023
Circumradius: R = 14.00216570989

Vertex coordinates: A[28; 0] B[0; 0] C[3.71442857143; 9.28546153196]
Centroid: CG[10.57114285714; 3.09548717732]
Coordinates of the circumscribed circle: U[14; -0.21554101092]
Coordinates of the inscribed circle: I[6; 4.06220192023]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 159.0787760317° = 159°4'40″ = 0.36551619694 rad
∠ B' = β' = 111.8043747989° = 111°48'13″ = 1.19902491351 rad
∠ C' = γ' = 89.11884916932° = 89°7'7″ = 1.58661815491 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.