# 4 8 11 triangle

### Obtuse scalene triangle.

Sides: a = 4   b = 8   c = 11

Area: T = 12.28656623753
Perimeter: p = 23
Semiperimeter: s = 11.5

Angle ∠ A = α = 16.2143633496° = 16°12'49″ = 0.28329812882 rad
Angle ∠ B = β = 33.9487926527° = 33°56'53″ = 0.59325030921 rad
Angle ∠ C = γ = 129.8388439977° = 129°50'18″ = 2.26661082733 rad

Height: ha = 6.14328311877
Height: hb = 3.07114155938
Height: hc = 2.23437567955

Median: ma = 9.40774438611
Median: mb = 7.24656883731
Median: mc = 3.12224989992

Inradius: r = 1.06883184674
Circumradius: R = 7.16328209625

Vertex coordinates: A[11; 0] B[0; 0] C[3.31881818182; 2.23437567955]
Centroid: CG[4.77327272727; 0.74545855985]
Coordinates of the circumscribed circle: U[5.5; -4.58986821791]
Coordinates of the inscribed circle: I[3.5; 1.06883184674]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 163.7866366504° = 163°47'11″ = 0.28329812882 rad
∠ B' = β' = 146.0522073473° = 146°3'7″ = 0.59325030921 rad
∠ C' = γ' = 50.1621560023° = 50°9'42″ = 2.26661082733 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.