# 15 28 30 triangle

### Acute scalene triangle.

Sides: a = 15   b = 28   c = 30

Area: T = 208.2244488233
Perimeter: p = 73
Semiperimeter: s = 36.5

Angle ∠ A = α = 29.72107087751° = 29°43'15″ = 0.51987242242 rad
Angle ∠ B = β = 67.73551251499° = 67°44'6″ = 1.18222009531 rad
Angle ∠ C = γ = 82.5444166075° = 82°32'39″ = 1.44106674763 rad

Height: ha = 27.76332650978
Height: hb = 14.87331777309
Height: hc = 13.88216325489

Median: ma = 28.03112325808
Median: mb = 19.14441897191
Median: mc = 16.71882534973

Inradius: r = 5.70547804995
Circumradius: R = 15.12879036713

Vertex coordinates: A[30; 0] B[0; 0] C[5.68333333333; 13.88216325489]
Centroid: CG[11.89444444444; 4.62772108496]
Coordinates of the circumscribed circle: U[15; 1.96330255954]
Coordinates of the inscribed circle: I[8.5; 5.70547804995]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 150.2799291225° = 150°16'45″ = 0.51987242242 rad
∠ B' = β' = 112.265487485° = 112°15'54″ = 1.18222009531 rad
∠ C' = γ' = 97.4565833925° = 97°27'21″ = 1.44106674763 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.