# 7 11 12 triangle

### Acute scalene triangle.

Sides: a = 7   b = 11   c = 12

Area: T = 37.9477331922
Perimeter: p = 30
Semiperimeter: s = 15

Angle ∠ A = α = 35.09768012276° = 35°5'48″ = 0.61325547383 rad
Angle ∠ B = β = 64.62330664748° = 64°37'23″ = 1.12878852827 rad
Angle ∠ C = γ = 80.28801322976° = 80°16'48″ = 1.40111526325 rad

Height: ha = 10.84220948349
Height: hb = 6.98995148949
Height: hc = 6.32545553203

Median: ma = 10.96658560997
Median: mb = 8.1399410298
Median: mc = 7

Inradius: r = 2.53298221281
Circumradius: R = 6.08773844958

Vertex coordinates: A[12; 0] B[0; 0] C[3; 6.32545553203]
Centroid: CG[5; 2.10881851068]
Coordinates of the circumscribed circle: U[6; 1.02877402396]
Coordinates of the inscribed circle: I[4; 2.53298221281]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 144.9033198772° = 144°54'12″ = 0.61325547383 rad
∠ B' = β' = 115.3776933525° = 115°22'37″ = 1.12878852827 rad
∠ C' = γ' = 99.72198677024° = 99°43'12″ = 1.40111526325 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.