# Isosceles triangle calculator (A,b)

Please enter two properties of the isosceles triangle

Use symbols: a, b, h, T, p, A, B, C, r, R

You have entered side b and angle α.

### Obtuse isosceles triangle.

Sides: a = 8.28113312084   b = 8.28113312084   c = 12.5

Area: T = 33.95765131959
Perimeter: p = 29.06326624169
Semiperimeter: s = 14.53113312084

Angle ∠ A = α = 41° = 0.71655849933 rad
Angle ∠ B = β = 41° = 0.71655849933 rad
Angle ∠ C = γ = 98° = 1.7110422667 rad

Height: ha = 8.20107378624
Height: hb = 8.20107378624
Height: hc = 5.43330421114

Median: ma = 9.76106409444
Median: mb = 9.76106409444
Median: mc = 5.43330421114

Inradius: r = 2.33767792468
Circumradius: R = 6.31114223282

Vertex coordinates: A[12.5; 0] B[0; 0] C[6.25; 5.43330421114]
Centroid: CG[6.25; 1.81110140371]
Coordinates of the circumscribed circle: U[6.25; -0.87883802169]
Coordinates of the inscribed circle: I[6.25; 2.33767792468]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 139° = 0.71655849933 rad
∠ B' = β' = 139° = 0.71655849933 rad
∠ C' = γ' = 82° = 1.7110422667 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.