# 5 28 28 triangle

### Acute isosceles triangle.

Sides: a = 5   b = 28   c = 28

Area: T = 69.72204238369
Perimeter: p = 61
Semiperimeter: s = 30.5

Angle ∠ A = α = 10.24550321996° = 10°14'42″ = 0.17988095439 rad
Angle ∠ B = β = 84.87774839002° = 84°52'39″ = 1.48113915549 rad
Angle ∠ C = γ = 84.87774839002° = 84°52'39″ = 1.48113915549 rad

Height: ha = 27.88881695348
Height: hb = 4.98800302741
Height: hc = 4.98800302741

Median: ma = 27.88881695348
Median: mb = 14.44395290782
Median: mc = 14.44395290782

Inradius: r = 2.28659155356
Circumradius: R = 14.05661394505

Vertex coordinates: A[28; 0] B[0; 0] C[0.44664285714; 4.98800302741]
Centroid: CG[9.48221428571; 1.66600100914]
Coordinates of the circumscribed circle: U[14; 1.25550124509]
Coordinates of the inscribed circle: I[2.5; 2.28659155356]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 169.75549678° = 169°45'18″ = 0.17988095439 rad
∠ B' = β' = 95.12325160998° = 95°7'21″ = 1.48113915549 rad
∠ C' = γ' = 95.12325160998° = 95°7'21″ = 1.48113915549 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.