# 14 18 18 triangle

### Acute isosceles triangle.

Sides: a = 14   b = 18   c = 18

Area: T = 116.0821867662
Perimeter: p = 50
Semiperimeter: s = 25

Angle ∠ A = α = 45.77107609523° = 45°46'15″ = 0.79988504798 rad
Angle ∠ B = β = 67.11546195238° = 67°6'53″ = 1.17113710869 rad
Angle ∠ C = γ = 67.11546195238° = 67°6'53″ = 1.17113710869 rad

Height: ha = 16.58331239518
Height: hb = 12.89879852958
Height: hc = 12.89879852958

Median: ma = 16.58331239518
Median: mb = 13.37990881603
Median: mc = 13.37990881603

Inradius: r = 4.64332747065
Circumradius: R = 9.76989675643

Vertex coordinates: A[18; 0] B[0; 0] C[5.44444444444; 12.89879852958]
Centroid: CG[7.81548148148; 4.29993284319]
Coordinates of the circumscribed circle: U[9; 3.79990429417]
Coordinates of the inscribed circle: I[7; 4.64332747065]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 134.2299239048° = 134°13'45″ = 0.79988504798 rad
∠ B' = β' = 112.8855380476° = 112°53'7″ = 1.17113710869 rad
∠ C' = γ' = 112.8855380476° = 112°53'7″ = 1.17113710869 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.