# 21 24 25 triangle

### Acute scalene triangle.

Sides: a = 21   b = 24   c = 25

Area: T = 232.1643735325
Perimeter: p = 70
Semiperimeter: s = 35

Angle ∠ A = α = 50.70435197608° = 50°42'13″ = 0.88549433622 rad
Angle ∠ B = β = 62.18218607153° = 62°10'55″ = 1.08552782045 rad
Angle ∠ C = γ = 67.11546195238° = 67°6'53″ = 1.17113710869 rad

Height: ha = 22.11108319357
Height: hb = 19.34769779437
Height: hc = 18.5733098826

Median: ma = 22.14215898255
Median: mb = 19.72330829233
Median: mc = 18.76883243791

Inradius: r = 6.63332495807
Circumradius: R = 13.5688010506

Vertex coordinates: A[25; 0] B[0; 0] C[9.8; 18.5733098826]
Centroid: CG[11.6; 6.1911032942]
Coordinates of the circumscribed circle: U[12.5; 5.27664485301]
Coordinates of the inscribed circle: I[11; 6.63332495807]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 129.2966480239° = 129°17'47″ = 0.88549433622 rad
∠ B' = β' = 117.8188139285° = 117°49'5″ = 1.08552782045 rad
∠ C' = γ' = 112.8855380476° = 112°53'7″ = 1.17113710869 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.