# 7 14 20 triangle

### Obtuse scalene triangle.

Sides: a = 7   b = 14   c = 20

Area: T = 29.99106235347
Perimeter: p = 41
Semiperimeter: s = 20.5

Angle ∠ A = α = 12.37696965171° = 12°22'11″ = 0.21658919317 rad
Angle ∠ B = β = 25.36884394418° = 25°22'6″ = 0.44327627944 rad
Angle ∠ C = γ = 142.2621864041° = 142°15'43″ = 2.48329379275 rad

Height: ha = 8.56987495813
Height: hb = 4.28443747907
Height: hc = 2.99990623535

Median: ma = 16.90441415044
Median: mb = 13.24876412995
Median: mc = 4.74334164903

Inradius: r = 1.46329572456
Circumradius: R = 16.33884398938

Vertex coordinates: A[20; 0] B[0; 0] C[6.325; 2.99990623535]
Centroid: CG[8.775; 10.9996874512]
Coordinates of the circumscribed circle: U[10; -12.92107050181]
Coordinates of the inscribed circle: I[6.5; 1.46329572456]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 167.6330303483° = 167°37'49″ = 0.21658919317 rad
∠ B' = β' = 154.6321560558° = 154°37'54″ = 0.44327627944 rad
∠ C' = γ' = 37.73881359589° = 37°44'17″ = 2.48329379275 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.