# 4 13 16 triangle

### Obtuse scalene triangle.

Sides: a = 4   b = 13   c = 16

Area: T = 18.9988355192
Perimeter: p = 33
Semiperimeter: s = 16.5

Angle ∠ A = α = 10.52656968806° = 10°31'33″ = 0.18437080666 rad
Angle ∠ B = β = 36.42199137286° = 36°25'12″ = 0.63656474079 rad
Angle ∠ C = γ = 133.0544389391° = 133°3'16″ = 2.32222371791 rad

Height: ha = 9.4999177596
Height: hb = 2.92328238757
Height: hc = 2.3754794399

Median: ma = 14.44395290782
Median: mb = 9.68224583655
Median: mc = 5.3398539126

Inradius: r = 1.15114154662
Circumradius: R = 10.94883162041

Vertex coordinates: A[16; 0] B[0; 0] C[3.219875; 2.3754794399]
Centroid: CG[6.406625; 0.7921598133]
Coordinates of the circumscribed circle: U[8; -7.47443312547]
Coordinates of the inscribed circle: I[3.5; 1.15114154662]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 169.4744303119° = 169°28'27″ = 0.18437080666 rad
∠ B' = β' = 143.5880086271° = 143°34'48″ = 0.63656474079 rad
∠ C' = γ' = 46.94656106092° = 46°56'44″ = 2.32222371791 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.