WOLFRAM|DEMONSTRATIONS PROJECT

The Incircle and the Altitudes of a Triangle

​
AA'
≈
1.59
BB'
≈
1.79
CC'
≈
1.71
r
≈
0.56
1
AA'
+
1
BB'
+
1
CC'
≈
1.77
1
r
≈
1.77
Let ABC be a triangle, AA', BB', and CC' be the altitudes, and
r
the inradius. Then
1
AA'
+
1
BB'
+
1
CC'
=
1
r
.