# 17 18 30 triangle

### Obtuse scalene triangle.

Sides: a = 17   b = 18   c = 30

Area: T = 135.1333036301
Perimeter: p = 65
Semiperimeter: s = 32.5

Angle ∠ A = α = 30.03326039163° = 30°1'57″ = 0.52441678213 rad
Angle ∠ B = β = 32.00109601588° = 32°3″ = 0.55985221186 rad
Angle ∠ C = γ = 117.9666435925° = 117°57'59″ = 2.05989027137 rad

Height: ha = 15.89880042707
Height: hb = 15.01547818113
Height: hc = 9.00988690868

Median: ma = 23.2332520311
Median: mb = 22.66105383872
Median: mc = 9.02877350426

Inradius: r = 4.15879395785
Circumradius: R = 16.98332637734

Vertex coordinates: A[30; 0] B[0; 0] C[14.41766666667; 9.00988690868]
Centroid: CG[14.80655555556; 3.00329563623]
Coordinates of the circumscribed circle: U[15; -7.96443736976]
Coordinates of the inscribed circle: I[14.5; 4.15879395785]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 149.9677396084° = 149°58'3″ = 0.52441678213 rad
∠ B' = β' = 147.9999039841° = 147°59'57″ = 0.55985221186 rad
∠ C' = γ' = 62.0343564075° = 62°2'1″ = 2.05989027137 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.