# 9 10 15 triangle

### Obtuse scalene triangle.

Sides: a = 9   b = 10   c = 15

Area: T = 43.63548484585
Perimeter: p = 34
Semiperimeter: s = 17

Angle ∠ A = α = 35.57771025511° = 35°34'38″ = 0.62109375778 rad
Angle ∠ B = β = 40.274389294° = 40°16'26″ = 0.70329120344 rad
Angle ∠ C = γ = 104.1499004509° = 104°8'56″ = 1.81877430414 rad

Height: ha = 9.69766329908
Height: hb = 8.72769696917
Height: hc = 5.81879797945

Median: ma = 11.92768604419
Median: mb = 11.3143708499
Median: mc = 5.85223499554

Inradius: r = 2.56767557917
Circumradius: R = 7.73546435687

Vertex coordinates: A[15; 0] B[0; 0] C[6.86766666667; 5.81879797945]
Centroid: CG[7.28988888889; 1.93993265982]
Coordinates of the circumscribed circle: U[7.5; -1.89106906501]
Coordinates of the inscribed circle: I[7; 2.56767557917]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 144.4232897449° = 144°25'22″ = 0.62109375778 rad
∠ B' = β' = 139.726610706° = 139°43'34″ = 0.70329120344 rad
∠ C' = γ' = 75.85109954911° = 75°51'4″ = 1.81877430414 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.