# 17 20 25 triangle

### Acute scalene triangle.

Sides: a = 17   b = 20   c = 25

Area: T = 169.2455383984
Perimeter: p = 62
Semiperimeter: s = 31

Angle ∠ A = α = 42.60882175298° = 42°36'30″ = 0.74436536843 rad
Angle ∠ B = β = 52.79223196383° = 52°47'32″ = 0.92113997975 rad
Angle ∠ C = γ = 84.59994628319° = 84°35'58″ = 1.47765391718 rad

Height: ha = 19.91112216452
Height: hb = 16.92545383984
Height: hc = 13.54396307187

Median: ma = 20.98221352584
Median: mb = 18.89444436277
Median: mc = 13.7220422734

Inradius: r = 5.46595285156
Circumradius: R = 12.55657338698

Vertex coordinates: A[25; 0] B[0; 0] C[10.28; 13.54396307187]
Centroid: CG[11.76; 4.51332102396]
Coordinates of the circumscribed circle: U[12.5; 1.18217161289]
Coordinates of the inscribed circle: I[11; 5.46595285156]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 137.392178247° = 137°23'30″ = 0.74436536843 rad
∠ B' = β' = 127.2087680362° = 127°12'28″ = 0.92113997975 rad
∠ C' = γ' = 95.40105371681° = 95°24'2″ = 1.47765391718 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.