If two circles E and F are inscribed in the arbelos tangent to the line segment CD, one on each side as shown in the figure, then the two circles, called Archimedean twins, are congruent.
"Arbelos" means shoemaker's knife in Greek.
Books of Lemmas Index
Proposition 1
Proposition 2
Proposition 3
Proposition 4
Proposition 5
Proposition 6
Proposition 7
Proposition 8
Proposition 9
Proposition 10
Proposition 11
Proposition 12
Proposition 13
Proposition 14
Proposition 15
