# 6 11 15 triangle

### Obtuse scalene triangle.

Sides: a = 6   b = 11   c = 15

Area: T = 28.28442712475
Perimeter: p = 32
Semiperimeter: s = 16

Angle ∠ A = α = 20.05499757242° = 20°3' = 0.35499380913 rad
Angle ∠ B = β = 38.9422441269° = 38°56'33″ = 0.68796738189 rad
Angle ∠ C = γ = 121.0087583007° = 121°27″ = 2.11219807434 rad

Height: ha = 9.42880904158
Height: hb = 5.14325947723
Height: hc = 3.77112361663

Median: ma = 12.80662484749
Median: mb = 10.01224921973
Median: mc = 4.7176990566

Inradius: r = 1.7687766953
Circumradius: R = 8.75504464172

Vertex coordinates: A[15; 0] B[0; 0] C[4.66766666667; 3.77112361663]
Centroid: CG[6.55655555556; 1.25770787221]
Coordinates of the circumscribed circle: U[7.5; -4.50878057301]
Coordinates of the inscribed circle: I[5; 1.7687766953]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 159.9550024276° = 159°57' = 0.35499380913 rad
∠ B' = β' = 141.0587558731° = 141°3'27″ = 0.68796738189 rad
∠ C' = γ' = 58.99224169931° = 58°59'33″ = 2.11219807434 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.