# 21 23 27 triangle

### Acute scalene triangle.

Sides: a = 21   b = 23   c = 27

Area: T = 233.8643608755
Perimeter: p = 71
Semiperimeter: s = 35.5

Angle ∠ A = α = 48.86769371798° = 48°52'1″ = 0.85328889492 rad
Angle ∠ B = β = 55.58799483259° = 55°34'48″ = 0.97700530964 rad
Angle ∠ C = γ = 75.55331144943° = 75°33'11″ = 1.31986506081 rad

Height: ha = 22.27327246434
Height: hb = 20.33659659787
Height: hc = 17.32332302782

Median: ma = 22.77660839479
Median: mb = 21.2787922831
Median: mc = 17.43997126413

Inradius: r = 6.58877072889
Circumradius: R = 13.94108179723

Vertex coordinates: A[27; 0] B[0; 0] C[11.87703703704; 17.32332302782]
Centroid: CG[12.95767901235; 5.77444100927]
Coordinates of the circumscribed circle: U[13.5; 3.47879887488]
Coordinates of the inscribed circle: I[12.5; 6.58877072889]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 131.133306282° = 131°7'59″ = 0.85328889492 rad
∠ B' = β' = 124.4220051674° = 124°25'12″ = 0.97700530964 rad
∠ C' = γ' = 104.4476885506° = 104°26'49″ = 1.31986506081 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.