# 6 28 30 triangle

### Obtuse scalene triangle.

Sides: a = 6   b = 28   c = 30

Area: T = 81.58443122175
Perimeter: p = 64
Semiperimeter: s = 32

Angle ∠ A = α = 11.20108183696° = 11°12'3″ = 0.19554911595 rad
Angle ∠ B = β = 65.02550346323° = 65°1'30″ = 1.13549009506 rad
Angle ∠ C = γ = 103.7744146998° = 103°46'27″ = 1.81112005436 rad

Height: ha = 27.19547707392
Height: hb = 5.82774508727
Height: hc = 5.43989541478

Median: ma = 28.86217393793
Median: mb = 16.49224225025
Median: mc = 13.60114705087

Inradius: r = 2.55495097568
Circumradius: R = 15.44441456421

Vertex coordinates: A[30; 0] B[0; 0] C[2.53333333333; 5.43989541478]
Centroid: CG[10.84444444444; 1.81329847159]
Coordinates of the circumscribed circle: U[15; -3.67771775338]
Coordinates of the inscribed circle: I[4; 2.55495097568]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 168.799918163° = 168°47'57″ = 0.19554911595 rad
∠ B' = β' = 114.9754965368° = 114°58'30″ = 1.13549009506 rad
∠ C' = γ' = 76.2265853002° = 76°13'33″ = 1.81112005436 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    