# 16 17 20 triangle

### Acute scalene triangle.

Sides: a = 16   b = 17   c = 20

Area: T = 131.0879889762
Perimeter: p = 53
Semiperimeter: s = 26.5

Angle ∠ A = α = 50.44990073704° = 50°26'56″ = 0.8810501283 rad
Angle ∠ B = β = 55.01097173583° = 55°35″ = 0.96601006885 rad
Angle ∠ C = γ = 74.54112752713° = 74°32'29″ = 1.30109906821 rad

Height: ha = 16.38549862202
Height: hb = 15.42111635014
Height: hc = 13.10879889762

Median: ma = 16.74881342244
Median: mb = 15.99221855917
Median: mc = 13.13439255366

Inradius: r = 4.94664109344
Circumradius: R = 10.37553520275

Vertex coordinates: A[20; 0] B[0; 0] C[9.175; 13.10879889762]
Centroid: CG[9.725; 4.36993296587]
Coordinates of the circumscribed circle: U[10; 2.76554890514]
Coordinates of the inscribed circle: I[9.5; 4.94664109344]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 129.551099263° = 129°33'4″ = 0.8810501283 rad
∠ B' = β' = 124.9990282642° = 124°59'25″ = 0.96601006885 rad
∠ C' = γ' = 105.4598724729° = 105°27'31″ = 1.30109906821 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.