# 18 26 29 triangle

### Acute scalene triangle.

Sides: a = 18   b = 26   c = 29

Area: T = 230.599908391
Perimeter: p = 73
Semiperimeter: s = 36.5

Angle ∠ A = α = 37.71102558131° = 37°42'37″ = 0.65881681257 rad
Angle ∠ B = β = 62.07701092129° = 62°4'12″ = 1.08333277728 rad
Angle ∠ C = γ = 80.2219634974° = 80°13'11″ = 1.4400096755 rad

Height: ha = 25.62221204344
Height: hb = 17.738839107
Height: hc = 15.90333850972

Median: ma = 26.02988301696
Median: mb = 20.33546994077
Median: mc = 17.02220445305

Inradius: r = 6.31877831208
Circumradius: R = 14.71438485655

Vertex coordinates: A[29; 0] B[0; 0] C[8.43110344828; 15.90333850972]
Centroid: CG[12.47770114943; 5.30111283657]
Coordinates of the circumscribed circle: U[14.5; 2.49994678653]
Coordinates of the inscribed circle: I[10.5; 6.31877831208]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 142.2989744187° = 142°17'23″ = 0.65881681257 rad
∠ B' = β' = 117.9329890787° = 117°55'48″ = 1.08333277728 rad
∠ C' = γ' = 99.7880365026° = 99°46'49″ = 1.4400096755 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.