# 23 28 28 triangle

### Acute isosceles triangle.

Sides: a = 23   b = 28   c = 28

Area: T = 293.5888040458
Perimeter: p = 79
Semiperimeter: s = 39.5

Angle ∠ A = α = 48.49994260262° = 48°29'58″ = 0.84664746695 rad
Angle ∠ B = β = 65.75502869869° = 65°45'1″ = 1.14875589921 rad
Angle ∠ C = γ = 65.75502869869° = 65°45'1″ = 1.14875589921 rad

Height: ha = 25.52993948224
Height: hb = 20.97105743184
Height: hc = 20.97105743184

Median: ma = 25.52993948224
Median: mb = 21.45992637339
Median: mc = 21.45992637339

Inradius: r = 7.43326086192
Circumradius: R = 15.35548488997

Vertex coordinates: A[28; 0] B[0; 0] C[9.44664285714; 20.97105743184]
Centroid: CG[12.48221428571; 6.99901914395]
Coordinates of the circumscribed circle: U[14; 6.30664557981]
Coordinates of the inscribed circle: I[11.5; 7.43326086192]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 131.5010573974° = 131°30'2″ = 0.84664746695 rad
∠ B' = β' = 114.2549713013° = 114°14'59″ = 1.14875589921 rad
∠ C' = γ' = 114.2549713013° = 114°14'59″ = 1.14875589921 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.