# 10 28 30 triangle

### Obtuse scalene triangle.

Sides: a = 10   b = 28   c = 30

Area: T = 139.9432845476
Perimeter: p = 68
Semiperimeter: s = 34

Angle ∠ A = α = 19.46329509463° = 19°27'47″ = 0.34396925762 rad
Angle ∠ B = β = 68.98998039759° = 68°53'59″ = 1.20325284334 rad
Angle ∠ C = γ = 91.63772450778° = 91°38'14″ = 1.59993716441 rad

Height: ha = 27.98985690953
Height: hb = 9.9965917534
Height: hc = 9.33295230318

Median: ma = 28.58332118559
Median: mb = 17.43655957742
Median: mc = 14.73109198627

Inradius: r = 4.11659660434
Circumradius: R = 15.00661262

Vertex coordinates: A[30; 0] B[0; 0] C[3.6; 9.33295230318]
Centroid: CG[11.2; 3.11098410106]
Coordinates of the circumscribed circle: U[15; -0.42987464629]
Coordinates of the inscribed circle: I[6; 4.11659660434]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 160.5377049054° = 160°32'13″ = 0.34396925762 rad
∠ B' = β' = 111.1100196024° = 111°6'1″ = 1.20325284334 rad
∠ C' = γ' = 88.36327549222° = 88°21'46″ = 1.59993716441 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.