# 11 15 25 triangle

### Obtuse scalene triangle.

Sides: a = 11   b = 15   c = 25

Area: T = 44.05989094282
Perimeter: p = 51
Semiperimeter: s = 25.5

Angle ∠ A = α = 13.59904939668° = 13°35'26″ = 0.23771988667 rad
Angle ∠ B = β = 18.68988366206° = 18°41'20″ = 0.32661817324 rad
Angle ∠ C = γ = 147.7210669413° = 147°43'14″ = 2.57882120545 rad

Height: ha = 8.01107108051
Height: hb = 5.87545212571
Height: hc = 3.52547127543

Median: ma = 19.86883164863
Median: mb = 17.79774717306
Median: mc = 4.09326763859

Inradius: r = 1.72878003697
Circumradius: R = 23.40661626442

Vertex coordinates: A[25; 0] B[0; 0] C[10.42; 3.52547127543]
Centroid: CG[11.80766666667; 1.17549042514]
Coordinates of the circumscribed circle: U[12.5; -19.78988465992]
Coordinates of the inscribed circle: I[10.5; 1.72878003697]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 166.4109506033° = 166°24'34″ = 0.23771988667 rad
∠ B' = β' = 161.3111163379° = 161°18'40″ = 0.32661817324 rad
∠ C' = γ' = 32.27993305874° = 32°16'46″ = 2.57882120545 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.