# 3 15 17 triangle

### Obtuse scalene triangle.

Sides: a = 3   b = 15   c = 17

Area: T = 17.8109758561
Perimeter: p = 35
Semiperimeter: s = 17.5

Angle ∠ A = α = 8.03295831464° = 8°1'46″ = 0.14401426635 rad
Angle ∠ B = β = 44.30105298893° = 44°18'2″ = 0.77331901069 rad
Angle ∠ C = γ = 127.6769886964° = 127°40'12″ = 2.22882598832 rad

Height: ha = 11.8733172374
Height: hb = 2.37546344748
Height: hc = 2.09552657131

Median: ma = 15.96108896995
Median: mb = 9.63106801421
Median: mc = 6.69895440801

Inradius: r = 1.01877004892
Circumradius: R = 10.73884948171

Vertex coordinates: A[17; 0] B[0; 0] C[2.14770588235; 2.09552657131]
Centroid: CG[6.38223529412; 0.69884219044]
Coordinates of the circumscribed circle: U[8.5; -6.56224134993]
Coordinates of the inscribed circle: I[2.5; 1.01877004892]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 171.9770416854° = 171°58'14″ = 0.14401426635 rad
∠ B' = β' = 135.6999470111° = 135°41'58″ = 0.77331901069 rad
∠ C' = γ' = 52.33301130357° = 52°19'48″ = 2.22882598832 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.