# 3 11 11 triangle

### Acute isosceles triangle.

Sides: a = 3   b = 11   c = 11

Area: T = 16.34658710383
Perimeter: p = 25
Semiperimeter: s = 12.5

Angle ∠ A = α = 15.67549595262° = 15°40'30″ = 0.27435796538 rad
Angle ∠ B = β = 82.16325202369° = 82°9'45″ = 1.43440064999 rad
Angle ∠ C = γ = 82.16325202369° = 82°9'45″ = 1.43440064999 rad

Height: ha = 10.89772473589
Height: hb = 2.97219765524
Height: hc = 2.97219765524

Median: ma = 10.89772473589
Median: mb = 5.89549130613
Median: mc = 5.89549130613

Inradius: r = 1.30876696831
Circumradius: R = 5.55218607597

Vertex coordinates: A[11; 0] B[0; 0] C[0.40990909091; 2.97219765524]
Centroid: CG[3.8033030303; 0.99106588508]
Coordinates of the circumscribed circle: U[5.5; 0.75770719218]
Coordinates of the inscribed circle: I[1.5; 1.30876696831]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 164.3255040474° = 164°19'30″ = 0.27435796538 rad
∠ B' = β' = 97.83774797631° = 97°50'15″ = 1.43440064999 rad
∠ C' = γ' = 97.83774797631° = 97°50'15″ = 1.43440064999 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.