# 15 25 30 triangle

### Obtuse scalene triangle.

Sides: a = 15   b = 25   c = 30

Area: T = 187.0832869339
Perimeter: p = 70
Semiperimeter: s = 35

Angle ∠ A = α = 29.92664348666° = 29°55'35″ = 0.52223148218 rad
Angle ∠ B = β = 56.25110114041° = 56°15'4″ = 0.98217653566 rad
Angle ∠ C = γ = 93.82325537293° = 93°49'21″ = 1.63875124752 rad

Height: ha = 24.94443825785
Height: hb = 14.96766295471
Height: hc = 12.47221912892

Median: ma = 26.57553645318
Median: mb = 20.15656443707
Median: mc = 14.14221356237

Inradius: r = 5.34552248382
Circumradius: R = 15.03334448576

Vertex coordinates: A[30; 0] B[0; 0] C[8.33333333333; 12.47221912892]
Centroid: CG[12.77877777778; 4.15773970964]
Coordinates of the circumscribed circle: U[15; -1.00222296572]
Coordinates of the inscribed circle: I[10; 5.34552248382]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 150.0743565133° = 150°4'25″ = 0.52223148218 rad
∠ B' = β' = 123.7498988596° = 123°44'56″ = 0.98217653566 rad
∠ C' = γ' = 86.17774462707° = 86°10'39″ = 1.63875124752 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.