# 13 18 24 triangle

### Obtuse scalene triangle.

Sides: a = 13   b = 18   c = 24

Area: T = 115.1455288657
Perimeter: p = 55
Semiperimeter: s = 27.5

Angle ∠ A = α = 32.21437979172° = 32°12'50″ = 0.56222368382 rad
Angle ∠ B = β = 47.57107345118° = 47°34'15″ = 0.83302659448 rad
Angle ∠ C = γ = 100.2155467571° = 100°12'56″ = 1.74990898705 rad

Height: ha = 17.71546597934
Height: hb = 12.79439209619
Height: hc = 9.59554407215

Median: ma = 20.19328205063
Median: mb = 17.0733371079
Median: mc = 10.12442283657

Inradius: r = 4.18771014057
Circumradius: R = 12.19332908968

Vertex coordinates: A[24; 0] B[0; 0] C[8.77108333333; 9.59554407215]
Centroid: CG[10.92436111111; 3.19884802405]
Coordinates of the circumscribed circle: U[12; -2.16224853514]
Coordinates of the inscribed circle: I[9.5; 4.18771014057]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 147.7866202083° = 147°47'10″ = 0.56222368382 rad
∠ B' = β' = 132.4299265488° = 132°25'45″ = 0.83302659448 rad
∠ C' = γ' = 79.7854532429° = 79°47'4″ = 1.74990898705 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.