# 25 26 29 triangle

### Acute scalene triangle.

Sides: a = 25   b = 26   c = 29

Area: T = 303.9743683071
Perimeter: p = 80
Semiperimeter: s = 40

Angle ∠ A = α = 53.73656266464° = 53°44'8″ = 0.93878636106 rad
Angle ∠ B = β = 56.98771177352° = 56°59'14″ = 0.99546128357 rad
Angle ∠ C = γ = 69.27772556184° = 69°16'38″ = 1.20991162073 rad

Height: ha = 24.31878946457
Height: hb = 23.38325910055
Height: hc = 20.96437022808

Median: ma = 24.54107823836
Median: mb = 23.74986841741
Median: mc = 20.98221352584

Inradius: r = 7.59993420768
Circumradius: R = 15.50329868125

Vertex coordinates: A[29; 0] B[0; 0] C[13.62106896552; 20.96437022808]
Centroid: CG[14.20768965517; 6.98879007603]
Coordinates of the circumscribed circle: U[14.5; 5.48656722567]
Coordinates of the inscribed circle: I[14; 7.59993420768]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 126.2644373354° = 126°15'52″ = 0.93878636106 rad
∠ B' = β' = 123.0132882265° = 123°46″ = 0.99546128357 rad
∠ C' = γ' = 110.7232744382° = 110°43'22″ = 1.20991162073 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    