# 9 24 26 triangle

### Obtuse scalene triangle.

Sides: a = 9   b = 24   c = 26

Area: T = 107.8955493418
Perimeter: p = 59
Semiperimeter: s = 29.5

Angle ∠ A = α = 20.23217918143° = 20°13'54″ = 0.35331113807 rad
Angle ∠ B = β = 67.24774417914° = 67°14'51″ = 1.17436892728 rad
Angle ∠ C = γ = 92.52107663943° = 92°31'15″ = 1.6154792 rad

Height: ha = 23.97767763152
Height: hb = 8.99112911182
Height: hc = 8.32996533399

Median: ma = 24.61219889485
Median: mb = 15.31333928311
Median: mc = 12.62993309403

Inradius: r = 3.65774743532
Circumradius: R = 13.01325916803

Vertex coordinates: A[26; 0] B[0; 0] C[3.48107692308; 8.32996533399]
Centroid: CG[9.82769230769; 2.76765511133]
Coordinates of the circumscribed circle: U[13; -0.572231306]
Coordinates of the inscribed circle: I[5.5; 3.65774743532]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 159.7688208186° = 159°46'6″ = 0.35331113807 rad
∠ B' = β' = 112.7532558209° = 112°45'9″ = 1.17436892728 rad
∠ C' = γ' = 87.47992336057° = 87°28'45″ = 1.6154792 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    