# 24 25 28 triangle

### Acute scalene triangle.

Sides: a = 24   b = 25   c = 28

Area: T = 281.3043994817
Perimeter: p = 77
Semiperimeter: s = 38.5

Angle ∠ A = α = 53.48773679008° = 53°29'15″ = 0.93435306781 rad
Angle ∠ B = β = 56.84771120714° = 56°50'50″ = 0.99221692759 rad
Angle ∠ C = γ = 69.66655200278° = 69°39'56″ = 1.21658926996 rad

Height: ha = 23.44219995681
Height: hb = 22.50443195854
Height: hc = 20.09331424869

Median: ma = 23.67548812035
Median: mb = 22.88655849827
Median: mc = 20.11221853611

Inradius: r = 7.3076597268
Circumradius: R = 14.93304669588

Vertex coordinates: A[28; 0] B[0; 0] C[13.125; 20.09331424869]
Centroid: CG[13.70883333333; 6.69877141623]
Coordinates of the circumscribed circle: U[14; 5.18883372682]
Coordinates of the inscribed circle: I[13.5; 7.3076597268]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 126.5132632099° = 126°30'45″ = 0.93435306781 rad
∠ B' = β' = 123.1532887929° = 123°9'10″ = 0.99221692759 rad
∠ C' = γ' = 110.3344479972° = 110°20'4″ = 1.21658926996 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    