# 13 20 24 triangle

### Obtuse scalene triangle.

Sides: a = 13   b = 20   c = 24

Area: T = 129.988822062
Perimeter: p = 57
Semiperimeter: s = 28.5

Angle ∠ A = α = 32.79438229603° = 32°47'38″ = 0.5722360185 rad
Angle ∠ B = β = 56.43548644036° = 56°26'5″ = 0.98549741968 rad
Angle ∠ C = γ = 90.77113126361° = 90°46'17″ = 1.58442582719 rad

Height: ha = 19.99881877877
Height: hb = 12.9998822062
Height: hc = 10.83223517183

Median: ma = 21.11327923307
Median: mb = 16.50875740192
Median: mc = 11.85332695911

Inradius: r = 4.56109901972
Circumradius: R = 12.00110874259

Vertex coordinates: A[24; 0] B[0; 0] C[7.18875; 10.83223517183]
Centroid: CG[10.39658333333; 3.61107839061]
Coordinates of the circumscribed circle: U[12; -0.16215531]
Coordinates of the inscribed circle: I[8.5; 4.56109901972]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 147.206617704° = 147°12'22″ = 0.5722360185 rad
∠ B' = β' = 123.5655135596° = 123°33'55″ = 0.98549741968 rad
∠ C' = γ' = 89.22986873639° = 89°13'43″ = 1.58442582719 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.