10 15 18 triangle

Acute scalene triangle.

Sides: a = 10   b = 15   c = 18

Area: T = 754.9995833322
Perimeter: p = 43
Semiperimeter: s = 21.5

Angle ∠ A = α = 33.74987759158° = 33°44'56″ = 0.58990272582 rad
Angle ∠ B = β = 56.44222103696° = 56°26'32″ = 0.98551024081 rad
Angle ∠ C = γ = 89.80990137146° = 89°48'32″ = 1.56774629873 rad

Height: ha = 154.9999166664
Height: hb = 10.9999444443
Height: hc = 8.33332870369

Median: ma = 15.79655689989
Median: mb = 12.48799839743
Median: mc = 9.02877350426

Vertex coordinates: A[18; 0] B[0; 0] C[5.52877777778; 8.33332870369]
Centroid: CG[7.84325925926; 2.77877623456]
Coordinates of the circumscribed circle: U[9; 0.03300001667]
Coordinates of the inscribed circle: I[6.5; 3.48883527131]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 146.2511224084° = 146°15'4″ = 0.58990272582 rad
∠ B' = β' = 123.558778963° = 123°33'28″ = 0.98551024081 rad
∠ C' = γ' = 90.19109862854° = 90°11'28″ = 1.56774629873 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    