# 11 25 28 triangle

### Obtuse scalene triangle.

Sides: a = 11   b = 25   c = 28

Area: T = 137.1711425596
Perimeter: p = 64
Semiperimeter: s = 32

Angle ∠ A = α = 23.07439180656° = 23°4'26″ = 0.40327158416 rad
Angle ∠ B = β = 62.96443082106° = 62°57'52″ = 1.09989344895 rad
Angle ∠ C = γ = 93.96217737238° = 93°57'42″ = 1.64399423225 rad

Height: ha = 24.94402591992
Height: hb = 10.97437140477
Height: hc = 9.79879589711

Median: ma = 25.96663243452
Median: mb = 17.21219144781
Median: mc = 13.30441346957

Inradius: r = 4.28766070499
Circumradius: R = 14.03435349847

Vertex coordinates: A[28; 0] B[0; 0] C[5; 9.79879589711]
Centroid: CG[11; 3.26659863237]
Coordinates of the circumscribed circle: U[14; -0.97695896899]
Coordinates of the inscribed circle: I[7; 4.28766070499]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 156.9266081934° = 156°55'34″ = 0.40327158416 rad
∠ B' = β' = 117.0365691789° = 117°2'8″ = 1.09989344895 rad
∠ C' = γ' = 86.03882262762° = 86°2'18″ = 1.64399423225 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.