# 8 12 12 triangle

### Acute isosceles triangle.

Sides: a = 8   b = 12   c = 12

Area: T = 45.25548339959
Perimeter: p = 32
Semiperimeter: s = 16

Angle ∠ A = α = 38.9422441269° = 38°56'33″ = 0.68796738189 rad
Angle ∠ B = β = 70.52987793655° = 70°31'44″ = 1.23109594173 rad
Angle ∠ C = γ = 70.52987793655° = 70°31'44″ = 1.23109594173 rad

Height: ha = 11.3143708499
Height: hb = 7.54224723327
Height: hc = 7.54224723327

Median: ma = 11.3143708499
Median: mb = 8.24662112512
Median: mc = 8.24662112512

Inradius: r = 2.82884271247
Circumradius: R = 6.36439610307

Vertex coordinates: A[12; 0] B[0; 0] C[2.66766666667; 7.54224723327]
Centroid: CG[4.88988888889; 2.51441574442]
Coordinates of the circumscribed circle: U[6; 2.12113203436]
Coordinates of the inscribed circle: I[4; 2.82884271247]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 141.0587558731° = 141°3'27″ = 0.68796738189 rad
∠ B' = β' = 109.4711220634° = 109°28'16″ = 1.23109594173 rad
∠ C' = γ' = 109.4711220634° = 109°28'16″ = 1.23109594173 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.