# 5 28 30 triangle

### Obtuse scalene triangle.

Sides: a = 5   b = 28   c = 30

Area: T = 66.21999811178
Perimeter: p = 63
Semiperimeter: s = 31.5

Angle ∠ A = α = 9.0698721546° = 9°4'7″ = 0.15882790499 rad
Angle ∠ B = β = 61.96657034651° = 61°57'57″ = 1.08215055488 rad
Angle ∠ C = γ = 108.9665574989° = 108°57'56″ = 1.90218080549 rad

Height: ha = 26.48799924471
Height: hb = 4.72985700798
Height: hc = 4.41333320745

Median: ma = 28.90993410509
Median: mb = 16.32548277173
Median: mc = 13.3987761007

Inradius: r = 2.10215867022
Circumradius: R = 15.86110317144

Vertex coordinates: A[30; 0] B[0; 0] C[2.35; 4.41333320745]
Centroid: CG[10.78333333333; 1.47111106915]
Coordinates of the circumscribed circle: U[15; -5.15548353072]
Coordinates of the inscribed circle: I[3.5; 2.10215867022]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 170.9311278454° = 170°55'53″ = 0.15882790499 rad
∠ B' = β' = 118.0344296535° = 118°2'3″ = 1.08215055488 rad
∠ C' = γ' = 71.03444250112° = 71°2'4″ = 1.90218080549 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.