# 20 29 30 triangle

### Acute scalene triangle.

Sides: a = 20   b = 29   c = 30

Area: T = 277.1876647406
Perimeter: p = 79
Semiperimeter: s = 39.5

Angle ∠ A = α = 39.58441402624° = 39°35'3″ = 0.69108735792 rad
Angle ∠ B = β = 67.51113753665° = 67°30'41″ = 1.17882957827 rad
Angle ∠ C = γ = 72.90444843711° = 72°54'16″ = 1.27224232917 rad

Height: ha = 27.71986647406
Height: hb = 19.11663205107
Height: hc = 18.4799109827

Median: ma = 27.75878817636
Median: mb = 20.97702169755
Median: mc = 19.88771818014

Inradius: r = 7.01773834786
Circumradius: R = 15.69333966362

Vertex coordinates: A[30; 0] B[0; 0] C[7.65; 18.4799109827]
Centroid: CG[12.55; 6.16597032757]
Coordinates of the circumscribed circle: U[15; 4.61333174594]
Coordinates of the inscribed circle: I[10.5; 7.01773834786]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 140.4165859738° = 140°24'57″ = 0.69108735792 rad
∠ B' = β' = 112.4898624634° = 112°29'19″ = 1.17882957827 rad
∠ C' = γ' = 107.0965515629° = 107°5'44″ = 1.27224232917 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.