# 3 28 28 triangle

### Acute isosceles triangle.

Sides: a = 3   b = 28   c = 28

Area: T = 41.943968884
Perimeter: p = 59
Semiperimeter: s = 29.5

Angle ∠ A = α = 6.14217736222° = 6°8'30″ = 0.10771941716 rad
Angle ∠ B = β = 86.92991131889° = 86°55'45″ = 1.5177199241 rad
Angle ∠ C = γ = 86.92991131889° = 86°55'45″ = 1.5177199241 rad

Height: ha = 27.965979256
Height: hb = 2.996569206
Height: hc = 2.996569206

Median: ma = 27.965979256
Median: mb = 14.16598022585
Median: mc = 14.16598022585

Inradius: r = 1.42216843675
Circumradius: R = 14.022013263

Vertex coordinates: A[28; 0] B[0; 0] C[0.16107142857; 2.996569206]
Centroid: CG[9.38769047619; 0.999856402]
Coordinates of the circumscribed circle: U[14; 0.75110785338]
Coordinates of the inscribed circle: I[1.5; 1.42216843675]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 173.8588226378° = 173°51'30″ = 0.10771941716 rad
∠ B' = β' = 93.07108868111° = 93°4'15″ = 1.5177199241 rad
∠ C' = γ' = 93.07108868111° = 93°4'15″ = 1.5177199241 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.