# 8 28 30 triangle

### Obtuse scalene triangle.

Sides: a = 8   b = 28   c = 30

Area: T = 111.2432977306
Perimeter: p = 66
Semiperimeter: s = 33

Angle ∠ A = α = 15.35988855808° = 15°21'32″ = 0.26880631228 rad
Angle ∠ B = β = 67.9765687163° = 67°58'32″ = 1.18663995523 rad
Angle ∠ C = γ = 96.66554272562° = 96°39'56″ = 1.68771299785 rad

Height: ha = 27.81107443266
Height: hb = 7.94659269505
Height: hc = 7.41661984871

Median: ma = 28.74402157264
Median: mb = 16.91215345253
Median: mc = 14.10767359797

Inradius: r = 3.37109993123
Circumradius: R = 15.10220769192

Vertex coordinates: A[30; 0] B[0; 0] C[3; 7.41661984871]
Centroid: CG[11; 2.47220661624]
Coordinates of the circumscribed circle: U[15; -1.75329196424]
Coordinates of the inscribed circle: I[5; 3.37109993123]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 164.6411114419° = 164°38'28″ = 0.26880631228 rad
∠ B' = β' = 112.0244312837° = 112°1'28″ = 1.18663995523 rad
∠ C' = γ' = 83.33545727438° = 83°20'4″ = 1.68771299785 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.