# 23 27 28 triangle

### Acute scalene triangle.

Sides: a = 23   b = 27   c = 28

Area: T = 286.9988257834
Perimeter: p = 78
Semiperimeter: s = 39

Angle ∠ A = α = 49.39985335° = 49°23'55″ = 0.86221670552 rad
Angle ∠ B = β = 63.03769273045° = 63°2'13″ = 1.11002019318 rad
Angle ∠ C = γ = 67.56545391954° = 67°33'52″ = 1.17992236666 rad

Height: ha = 24.95663702465
Height: hb = 21.259913021
Height: hc = 20.54998755596

Median: ma = 24.98549954973
Median: mb = 21.77772817404
Median: mc = 20.80986520467

Inradius: r = 7.35989296881
Circumradius: R = 15.14664334063

Vertex coordinates: A[28; 0] B[0; 0] C[10.42985714286; 20.54998755596]
Centroid: CG[12.81095238095; 6.83332918532]
Coordinates of the circumscribed circle: U[14; 5.78105228942]
Coordinates of the inscribed circle: I[12; 7.35989296881]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 130.60114665° = 130°36'5″ = 0.86221670552 rad
∠ B' = β' = 116.9633072695° = 116°57'47″ = 1.11002019318 rad
∠ C' = γ' = 112.4355460805° = 112°26'8″ = 1.17992236666 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.