# 7 8 11 triangle

### Obtuse scalene triangle.

Sides: a = 7   b = 8   c = 11

Area: T = 27.92884800875
Perimeter: p = 26
Semiperimeter: s = 13

Angle ∠ A = α = 39.40105687537° = 39°24'2″ = 0.68876696519 rad
Angle ∠ B = β = 46.50333874881° = 46°30'12″ = 0.8121637225 rad
Angle ∠ C = γ = 94.09660437582° = 94°5'46″ = 1.64222857767 rad

Height: ha = 7.98795657393
Height: hb = 6.98221200219
Height: hc = 5.07879054705

Median: ma = 8.95882364336
Median: mb = 8.30766238629
Median: mc = 5.1233475383

Inradius: r = 2.14883446221
Circumradius: R = 5.51440845301

Vertex coordinates: A[11; 0] B[0; 0] C[4.81881818182; 5.07879054705]
Centroid: CG[5.27327272727; 1.69326351568]
Coordinates of the circumscribed circle: U[5.5; -0.39438631807]
Coordinates of the inscribed circle: I[5; 2.14883446221]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 140.5999431246° = 140°35'58″ = 0.68876696519 rad
∠ B' = β' = 133.4976612512° = 133°29'48″ = 0.8121637225 rad
∠ C' = γ' = 85.90439562418° = 85°54'14″ = 1.64222857767 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.