# 15 17 30 triangle

### Obtuse scalene triangle.

Sides: a = 15   b = 17   c = 30

Area: T = 83.3310666624
Perimeter: p = 62
Semiperimeter: s = 31

Angle ∠ A = α = 19.07438706794° = 19°4'26″ = 0.33329018445 rad
Angle ∠ B = β = 21.73877297313° = 21°44'16″ = 0.37993949557 rad
Angle ∠ C = γ = 139.1888399589° = 139°11'18″ = 2.42992958534 rad

Height: ha = 11.11107555499
Height: hb = 9.80436078381
Height: hc = 5.55553777749

Median: ma = 23.22002155162
Median: mb = 22.14215898255
Median: mc = 5.65768542495

Inradius: r = 2.68880860201
Circumradius: R = 22.95107344353

Vertex coordinates: A[30; 0] B[0; 0] C[13.93333333333; 5.55553777749]
Centroid: CG[14.64444444444; 1.85217925916]
Coordinates of the circumscribed circle: U[15; -17.37105558667]
Coordinates of the inscribed circle: I[14; 2.68880860201]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 160.9266129321° = 160°55'34″ = 0.33329018445 rad
∠ B' = β' = 158.2622270269° = 158°15'44″ = 0.37993949557 rad
∠ C' = γ' = 40.81216004107° = 40°48'42″ = 2.42992958534 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.