# 4 15 16 triangle

### Obtuse scalene triangle.

Sides: a = 4   b = 15   c = 16

Area: T = 29.76547022495
Perimeter: p = 35
Semiperimeter: s = 17.5

Angle ∠ A = α = 14.36215115629° = 14°21'41″ = 0.25106556623 rad
Angle ∠ B = β = 68.45877326556° = 68°27'28″ = 1.19548128333 rad
Angle ∠ C = γ = 97.18107557815° = 97°10'51″ = 1.6966124158 rad

Height: ha = 14.88223511247
Height: hb = 3.96986269666
Height: hc = 3.72105877812

Median: ma = 15.37985564992
Median: mb = 8.93302855497
Median: mc = 7.51766481892

Inradius: r = 1.70108401285
Circumradius: R = 8.06332420909

Vertex coordinates: A[16; 0] B[0; 0] C[1.469875; 3.72105877812]
Centroid: CG[5.82329166667; 1.24401959271]
Coordinates of the circumscribed circle: U[8; -1.00879052614]
Coordinates of the inscribed circle: I[2.5; 1.70108401285]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 165.6388488437° = 165°38'19″ = 0.25106556623 rad
∠ B' = β' = 111.5422267344° = 111°32'32″ = 1.19548128333 rad
∠ C' = γ' = 82.81992442185° = 82°49'9″ = 1.6966124158 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.