# 20 27 27 triangle

### Acute isosceles triangle.

Sides: a = 20   b = 27   c = 27

Area: T = 250.799872408
Perimeter: p = 74
Semiperimeter: s = 37

Angle ∠ A = α = 43.4776921583° = 43°28'37″ = 0.75988154303 rad
Angle ∠ B = β = 68.26215392085° = 68°15'42″ = 1.19113886117 rad
Angle ∠ C = γ = 68.26215392085° = 68°15'42″ = 1.19113886117 rad

Height: ha = 25.0879872408
Height: hb = 18.57876832652
Height: hc = 18.57876832652

Median: ma = 25.0879872408
Median: mb = 19.5511214796
Median: mc = 19.5511214796

Inradius: r = 6.7788343894
Circumradius: R = 14.53435667611

Vertex coordinates: A[27; 0] B[0; 0] C[7.40774074074; 18.57876832652]
Centroid: CG[11.46991358025; 6.19325610884]
Coordinates of the circumscribed circle: U[13.5; 5.38328025041]
Coordinates of the inscribed circle: I[10; 6.7788343894]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 136.5233078417° = 136°31'23″ = 0.75988154303 rad
∠ B' = β' = 111.7388460792° = 111°44'18″ = 1.19113886117 rad
∠ C' = γ' = 111.7388460792° = 111°44'18″ = 1.19113886117 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.