# 13 14 15 triangle

### Acute scalene triangle.

Sides: a = 13   b = 14   c = 15

Area: T = 84
Perimeter: p = 42
Semiperimeter: s = 21

Angle ∠ A = α = 53.13301023542° = 53°7'48″ = 0.9277295218 rad
Angle ∠ B = β = 59.49897625939° = 59°29'23″ = 1.03882922285 rad
Angle ∠ C = γ = 67.3880135052° = 67°22'49″ = 1.17660052071 rad

Height: ha = 12.92330769231
Height: hb = 12
Height: hc = 11.2

Median: ma = 12.97111217711
Median: mb = 12.16655250606
Median: mc = 11.23661025271

Inradius: r = 4
Circumradius: R = 8.125

Vertex coordinates: A[15; 0] B[0; 0] C[6.6; 11.2]
Centroid: CG[7.2; 3.73333333333]
Coordinates of the circumscribed circle: U[7.5; 3.125]
Coordinates of the inscribed circle: I[7; 4]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 126.8769897646° = 126°52'12″ = 0.9277295218 rad
∠ B' = β' = 120.5110237406° = 120°30'37″ = 1.03882922285 rad
∠ C' = γ' = 112.6219864948° = 112°37'11″ = 1.17660052071 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.