# 1 15 15 triangle

### Acute isosceles triangle.

Sides: a = 1   b = 15   c = 15

Area: T = 7.49658321753
Perimeter: p = 31
Semiperimeter: s = 15.5

Angle ∠ A = α = 3.82204263434° = 3°49'14″ = 0.06766790185 rad
Angle ∠ B = β = 88.09897868283° = 88°5'23″ = 1.53774568175 rad
Angle ∠ C = γ = 88.09897868283° = 88°5'23″ = 1.53774568175 rad

Height: ha = 14.99216643506
Height: hb = 0.999944429
Height: hc = 0.999944429

Median: ma = 14.99216643506
Median: mb = 7.53332595867
Median: mc = 7.53332595867

Inradius: r = 0.48436020758
Circumradius: R = 7.50441701421

Vertex coordinates: A[15; 0] B[0; 0] C[0.03333333333; 0.999944429]
Centroid: CG[5.01111111111; 0.33331480967]
Coordinates of the circumscribed circle: U[7.5; 0.25501390047]
Coordinates of the inscribed circle: I[0.5; 0.48436020758]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 176.1879573657° = 176°10'46″ = 0.06766790185 rad
∠ B' = β' = 91.91102131717° = 91°54'37″ = 1.53774568175 rad
∠ C' = γ' = 91.91102131717° = 91°54'37″ = 1.53774568175 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.