# 8 8 12 triangle

### Obtuse isosceles triangle.

Sides: a = 8   b = 8   c = 12

Area: T = 31.74990157328
Perimeter: p = 28
Semiperimeter: s = 14

Angle ∠ A = α = 41.41096221093° = 41°24'35″ = 0.72327342478 rad
Angle ∠ B = β = 41.41096221093° = 41°24'35″ = 0.72327342478 rad
Angle ∠ C = γ = 97.18107557815° = 97°10'51″ = 1.6966124158 rad

Height: ha = 7.93772539332
Height: hb = 7.93772539332
Height: hc = 5.29215026221

Median: ma = 9.38108315196
Median: mb = 9.38108315196
Median: mc = 5.29215026221

Inradius: r = 2.26877868381
Circumradius: R = 6.04774315681

Vertex coordinates: A[12; 0] B[0; 0] C[6; 5.29215026221]
Centroid: CG[6; 1.76438342074]
Coordinates of the circumscribed circle: U[6; -0.7565928946]
Coordinates of the inscribed circle: I[6; 2.26877868381]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 138.5990377891° = 138°35'25″ = 0.72327342478 rad
∠ B' = β' = 138.5990377891° = 138°35'25″ = 0.72327342478 rad
∠ C' = γ' = 82.81992442185° = 82°49'9″ = 1.6966124158 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.