# 8 9 11 triangle

### Acute scalene triangle.

Sides: a = 8   b = 9   c = 11

Area: T = 35.49664786986
Perimeter: p = 28
Semiperimeter: s = 14

Angle ∠ A = α = 45.81656148467° = 45°48'56″ = 0.87996333279 rad
Angle ∠ B = β = 53.77884533802° = 53°46'42″ = 0.93986110781 rad
Angle ∠ C = γ = 80.40659317731° = 80°24'21″ = 1.40333482476 rad

Height: ha = 8.87441196746
Height: hb = 7.88881063775
Height: hc = 6.45439052179

Median: ma = 9.22195444573
Median: mb = 8.5
Median: mc = 6.5

Inradius: r = 2.53554627642
Circumradius: R = 5.57880180812

Vertex coordinates: A[11; 0] B[0; 0] C[4.72772727273; 6.45439052179]
Centroid: CG[5.24224242424; 2.15113017393]
Coordinates of the circumscribed circle: U[5.5; 0.93296696802]
Coordinates of the inscribed circle: I[5; 2.53554627642]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 134.1844385153° = 134°11'4″ = 0.87996333279 rad
∠ B' = β' = 126.222154662° = 126°13'18″ = 0.93986110781 rad
∠ C' = γ' = 99.59440682269° = 99°35'39″ = 1.40333482476 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.