# 8 20 23 triangle

### Obtuse scalene triangle.

Sides: a = 8   b = 20   c = 23

Area: T = 78.33222251695
Perimeter: p = 51
Semiperimeter: s = 25.5

Angle ∠ A = α = 19.91219034612° = 19°54'43″ = 0.34875282757 rad
Angle ∠ B = β = 58.3688336233° = 58°22'6″ = 1.01987196462 rad
Angle ∠ C = γ = 101.7219760306° = 101°43'11″ = 1.77553447317 rad

Height: ha = 19.58330562924
Height: hb = 7.83332225169
Height: hc = 6.81114978408

Median: ma = 21.17878185845
Median: mb = 14.01878457689
Median: mc = 9.98774921777

Inradius: r = 3.07218519674
Circumradius: R = 11.74548470027

Vertex coordinates: A[23; 0] B[0; 0] C[4.19656521739; 6.81114978408]
Centroid: CG[9.06552173913; 2.27704992803]
Coordinates of the circumscribed circle: U[11.5; -2.38656720474]
Coordinates of the inscribed circle: I[5.5; 3.07218519674]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 160.0888096539° = 160°5'17″ = 0.34875282757 rad
∠ B' = β' = 121.6321663767° = 121°37'54″ = 1.01987196462 rad
∠ C' = γ' = 78.28802396942° = 78°16'49″ = 1.77553447317 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.