# 153 90 179.91 triangle

### Obtuse scalene triangle.

Sides: a = 153   b = 90   c = 179.91

Area: T = 6881.653310868
Perimeter: p = 422.91
Semiperimeter: s = 211.455

Angle ∠ A = α = 58.21329538663° = 58°12'47″ = 1.01660077123 rad
Angle ∠ B = β = 300.0004595932° = 30°2″ = 0.5243606797 rad
Angle ∠ C = γ = 91.78765865405° = 91°47'12″ = 1.60219781443 rad

Height: ha = 89.95662497866
Height: hb = 152.9265624637
Height: hc = 76.50110628501

Median: ma = 119.9233117246
Median: mb = 160.8210720214
Median: mc = 87.5366266627

Inradius: r = 32.54442912614
Circumradius: R = 89.99987496055

Vertex coordinates: A[179.91; 0] B[0; 0] C[132.5011273137; 76.50110628501]
Centroid: CG[104.1377091046; 25.55003542834]
Coordinates of the circumscribed circle: U[89.955; -2.80658698403]
Coordinates of the inscribed circle: I[121.455; 32.54442912614]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 121.7877046134° = 121°47'13″ = 1.01660077123 rad
∠ B' = β' = 1509.999540407° = 149°59'58″ = 0.5243606797 rad
∠ C' = γ' = 88.21334134595° = 88°12'48″ = 1.60219781443 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    