# Triangle calculator SSS - result

Please enter the triangle sides:

### Acute isosceles triangle.

Sides: a = 21   b = 28   c = 28

Area: T = 272.5455294401
Perimeter: p = 77
Semiperimeter: s = 38.5

Angle ∠ A = α = 44.04986256741° = 44°2'55″ = 0.7698793549 rad
Angle ∠ B = β = 67.9765687163° = 67°58'32″ = 1.18663995523 rad
Angle ∠ C = γ = 67.9765687163° = 67°58'32″ = 1.18663995523 rad

Height: ha = 25.95766947048
Height: hb = 19.46875210286
Height: hc = 19.46875210286

Median: ma = 25.95766947048
Median: mb = 20.4088331632
Median: mc = 20.4088331632

Inradius: r = 7.07990985559
Circumradius: R = 15.10220769192

Vertex coordinates: A[28; 0] B[0; 0] C[7.875; 19.46875210286]
Centroid: CG[11.95883333333; 6.48991736762]
Coordinates of the circumscribed circle: U[14; 5.66332788447]
Coordinates of the inscribed circle: I[10.5; 7.07990985559]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 135.9511374326° = 135°57'5″ = 0.7698793549 rad
∠ B' = β' = 112.0244312837° = 112°1'28″ = 1.18663995523 rad
∠ C' = γ' = 112.0244312837° = 112°1'28″ = 1.18663995523 rad

# How did we calculate this triangle?

### 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.