# 14 21 30 triangle

### Obtuse scalene triangle.

Sides: a = 14   b = 21   c = 30

Area: T = 131.4765995908
Perimeter: p = 65
Semiperimeter: s = 32.5

Angle ∠ A = α = 24.67695454829° = 24°40'10″ = 0.43105647936 rad
Angle ∠ B = β = 38.76112192061° = 38°45'40″ = 0.67765108972 rad
Angle ∠ C = γ = 116.5699235311° = 116°34'9″ = 2.03545169627 rad

Height: ha = 18.78222851297
Height: hb = 12.52215234198
Height: hc = 8.76550663939

Median: ma = 24.93299017246
Median: mb = 20.92224759529
Median: mc = 9.67695398029

Inradius: r = 4.04554152587
Circumradius: R = 16.77111222476

Vertex coordinates: A[30; 0] B[0; 0] C[10.91766666667; 8.76550663939]
Centroid: CG[13.63988888889; 2.9221688798]
Coordinates of the circumscribed circle: U[15; -7.50113693046]
Coordinates of the inscribed circle: I[11.5; 4.04554152587]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 155.3330454517° = 155°19'50″ = 0.43105647936 rad
∠ B' = β' = 141.2398780794° = 141°14'20″ = 0.67765108972 rad
∠ C' = γ' = 63.4310764689° = 63°25'51″ = 2.03545169627 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.