# 6 8 9 triangle

### Acute scalene triangle.

Sides: a = 6   b = 8   c = 9

Area: T = 23.52552523897
Perimeter: p = 23
Semiperimeter: s = 11.5

Angle ∠ A = α = 40.80444376906° = 40°48'16″ = 0.71221717871 rad
Angle ∠ B = β = 60.61107200521° = 60°36'39″ = 1.05878566269 rad
Angle ∠ C = γ = 78.58548422573° = 78°35'5″ = 1.37215642395 rad

Height: ha = 7.84217507966
Height: hb = 5.88113130974
Height: hc = 5.22878338644

Median: ma = 7.96986887253
Median: mb = 6.51992024052
Median: mc = 5.45443560573

Inradius: r = 2.04656741208
Circumradius: R = 4.59108115335

Vertex coordinates: A[9; 0] B[0; 0] C[2.94444444444; 5.22878338644]
Centroid: CG[3.98114814815; 1.74326112881]
Coordinates of the circumscribed circle: U[4.5; 0.9098598116]
Coordinates of the inscribed circle: I[3.5; 2.04656741208]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 139.1965562309° = 139°11'44″ = 0.71221717871 rad
∠ B' = β' = 119.3899279948° = 119°23'21″ = 1.05878566269 rad
∠ C' = γ' = 101.4155157743° = 101°24'55″ = 1.37215642395 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.