WOLFRAM|DEMONSTRATIONS PROJECT

Crossed Ladders Theorem

​
length of EF
AB
≈
1.04
CD
≈
0.45
EF
≈
0.80
1
AB
+
1
EF
≈
2.21
1
CD
≈
2.21
Let AB and EF be parallel. Let D be the intersection of BE and AF. Let the parallel to AB through D intersect AE at C. Then
1
AB
+
1
EF
=
1
CD
.
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