# 11 20 27 triangle

### Obtuse scalene triangle.

Sides: a = 11   b = 20   c = 27

Area: T = 96.93329665284
Perimeter: p = 58
Semiperimeter: s = 29

Angle ∠ A = α = 21.03994697813° = 21°2'22″ = 0.36772080206 rad
Angle ∠ B = β = 40.74990543775° = 40°44'57″ = 0.7111205166 rad
Angle ∠ C = γ = 118.2111475841° = 118°12'41″ = 2.06331794671 rad

Height: ha = 17.62441757324
Height: hb = 9.69332966528
Height: hc = 7.18802197428

Median: ma = 23.11438486627
Median: mb = 18.02877563773
Median: mc = 8.84659030065

Inradius: r = 3.34325160872
Circumradius: R = 15.32198653996

Vertex coordinates: A[27; 0] B[0; 0] C[8.33333333333; 7.18802197428]
Centroid: CG[11.77877777778; 2.39334065809]
Coordinates of the circumscribed circle: U[13.5; -7.24221181889]
Coordinates of the inscribed circle: I[9; 3.34325160872]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 158.9610530219° = 158°57'38″ = 0.36772080206 rad
∠ B' = β' = 139.2510945623° = 139°15'3″ = 0.7111205166 rad
∠ C' = γ' = 61.78985241588° = 61°47'19″ = 2.06331794671 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.