# 23 26 28 triangle

### Acute scalene triangle.

Sides: a = 23   b = 26   c = 28

Area: T = 279.8633247855
Perimeter: p = 77
Semiperimeter: s = 38.5

Angle ∠ A = α = 50.251118676° = 50°15'4″ = 0.8777048662 rad
Angle ∠ B = β = 60.35989156325° = 60°21'32″ = 1.05334618107 rad
Angle ∠ C = γ = 69.39898976075° = 69°23'24″ = 1.21110821809 rad

Height: ha = 24.33659345961
Height: hb = 21.52879421427
Height: hc = 19.99902319896

Median: ma = 24.44989263568
Median: mb = 22.07994021658
Median: mc = 20.16218451537

Inradius: r = 7.2699175269
Circumradius: R = 14.95773051556

Vertex coordinates: A[28; 0] B[0; 0] C[11.375; 19.99902319896]
Centroid: CG[13.125; 6.66334106632]
Coordinates of the circumscribed circle: U[14; 5.26550714636]
Coordinates of the inscribed circle: I[12.5; 7.2699175269]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 129.749881324° = 129°44'56″ = 0.8777048662 rad
∠ B' = β' = 119.6411084367° = 119°38'28″ = 1.05334618107 rad
∠ C' = γ' = 110.6110102393° = 110°36'36″ = 1.21110821809 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.