# 18 22 25 triangle

### Acute scalene triangle.

Sides: a = 18   b = 22   c = 25

Area: T = 192.6421993086
Perimeter: p = 65
Semiperimeter: s = 32.5

Angle ∠ A = α = 44.46884446032° = 44°28'6″ = 0.77661207716 rad
Angle ∠ B = β = 58.89110774895° = 58°53'28″ = 1.02878432022 rad
Angle ∠ C = γ = 76.64404779074° = 76°38'26″ = 1.33876286798 rad

Height: ha = 21.40546658984
Height: hb = 17.51329084623
Height: hc = 15.41113594468

Median: ma = 21.7660055147
Median: mb = 18.8021595677
Median: mc = 15.74400762387

Inradius: r = 5.92774459411
Circumradius: R = 12.84876660792

Vertex coordinates: A[25; 0] B[0; 0] C[9.3; 15.41113594468]
Centroid: CG[11.43333333333; 5.13771198156]
Coordinates of the circumscribed circle: U[12.5; 2.96985895107]
Coordinates of the inscribed circle: I[10.5; 5.92774459411]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 135.5321555397° = 135°31'54″ = 0.77661207716 rad
∠ B' = β' = 121.1098922511° = 121°6'32″ = 1.02878432022 rad
∠ C' = γ' = 103.3659522093° = 103°21'34″ = 1.33876286798 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.