# 400 90 450 triangle

### Obtuse scalene triangle.

Sides: a = 400   b = 90   c = 450

Area: T = 15812.65331613
Perimeter: p = 940
Semiperimeter: s = 470

Angle ∠ A = α = 51.34404624624° = 51°20'26″ = 0.89660601095 rad
Angle ∠ B = β = 10.11991720527° = 10°7'9″ = 0.17766128699 rad
Angle ∠ C = γ = 118.5440365485° = 118°32'25″ = 2.06989196742 rad

Height: ha = 79.06332658066
Height: hb = 351.3922292474
Height: hc = 70.27884584947

Median: ma = 255.5398646784
Median: mb = 423.3549737215
Median: mc = 182.8255052988

Inradius: r = 33.64439428964
Circumradius: R = 256.1244001373

Vertex coordinates: A[450; 0] B[0; 0] C[393.7787777778; 70.27884584947]
Centroid: CG[281.2599259259; 23.42661528316]
Coordinates of the circumscribed circle: U[225; -122.3770356212]
Coordinates of the inscribed circle: I[380; 33.64439428964]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 128.6659537538° = 128°39'34″ = 0.89660601095 rad
∠ B' = β' = 169.8810827947° = 169°52'51″ = 0.17766128699 rad
∠ C' = γ' = 61.46596345151° = 61°27'35″ = 2.06989196742 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.