# 5 21 22 triangle

### Obtuse scalene triangle.

Sides: a = 5   b = 21   c = 22

Area: T = 52.30767873225
Perimeter: p = 48
Semiperimeter: s = 24

Angle ∠ A = α = 13.08773526646° = 13°5'14″ = 0.22884173944 rad
Angle ∠ B = β = 71.99655469999° = 71°59'44″ = 1.25765593419 rad
Angle ∠ C = γ = 94.91771003355° = 94°55'2″ = 1.65766159173 rad

Height: ha = 20.9232714929
Height: hb = 4.98215987926
Height: hc = 4.75551624839

Median: ma = 21.36600093633
Median: mb = 12.01104121495
Median: mc = 10.58330052443

Inradius: r = 2.17994494718
Circumradius: R = 11.04106321925

Vertex coordinates: A[22; 0] B[0; 0] C[1.54554545455; 4.75551624839]
Centroid: CG[7.84884848485; 1.58550541613]
Coordinates of the circumscribed circle: U[11; -0.94663399022]
Coordinates of the inscribed circle: I[3; 2.17994494718]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 166.9132647335° = 166°54'46″ = 0.22884173944 rad
∠ B' = β' = 108.0044453° = 108°16″ = 1.25765593419 rad
∠ C' = γ' = 85.08328996645° = 85°4'58″ = 1.65766159173 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.