# 13 14 18 triangle

### Acute scalene triangle.

Sides: a = 13   b = 14   c = 18

Area: T = 90.42108908383
Perimeter: p = 45
Semiperimeter: s = 22.5

Angle ∠ A = α = 45.85988345181° = 45°51'32″ = 0.88003876535 rad
Angle ∠ B = β = 50.60985359027° = 50°36'31″ = 0.88332855811 rad
Angle ∠ C = γ = 83.53326295792° = 83°31'57″ = 1.4587919419 rad

Height: ha = 13.91109062828
Height: hb = 12.91772701198
Height: hc = 10.04767656487

Median: ma = 14.75663545634
Median: mb = 14.05334693226
Median: mc = 10.07547208398

Inradius: r = 4.01987062595
Circumradius: R = 9.05876413526

Vertex coordinates: A[18; 0] B[0; 0] C[8.25; 10.04767656487]
Centroid: CG[8.75; 3.34989218829]
Coordinates of the circumscribed circle: U[9; 1.02202288337]
Coordinates of the inscribed circle: I[8.5; 4.01987062595]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 134.1411165482° = 134°8'28″ = 0.88003876535 rad
∠ B' = β' = 129.3911464097° = 129°23'29″ = 0.88332855811 rad
∠ C' = γ' = 96.46773704208° = 96°28'3″ = 1.4587919419 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.