# 4 10 13 triangle

### Obtuse scalene triangle.

Sides: a = 4   b = 10   c = 13

Area: T = 14.98112382666
Perimeter: p = 27
Semiperimeter: s = 13.5

Angle ∠ A = α = 13.3255367656° = 13°19'31″ = 0.23325715396 rad
Angle ∠ B = β = 35.18438154883° = 35°11'2″ = 0.61440734237 rad
Angle ∠ C = γ = 131.4910816856° = 131°29'27″ = 2.29549476903 rad

Height: ha = 7.49106191333
Height: hb = 2.99662476533
Height: hc = 2.30548058872

Median: ma = 11.42436596588
Median: mb = 8.21658383626
Median: mc = 3.96986269666

Inradius: r = 1.11097213531
Circumradius: R = 8.67875203549

Vertex coordinates: A[13; 0] B[0; 0] C[3.26992307692; 2.30548058872]
Centroid: CG[5.42330769231; 0.76882686291]
Coordinates of the circumscribed circle: U[6.5; -5.74988572351]
Coordinates of the inscribed circle: I[3.5; 1.11097213531]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 166.6754632344° = 166°40'29″ = 0.23325715396 rad
∠ B' = β' = 144.8166184512° = 144°48'58″ = 0.61440734237 rad
∠ C' = γ' = 48.50991831443° = 48°30'33″ = 2.29549476903 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.