Tangent and secant of a circle; the Pythagorean theorem
Circle tangent/secant constructions and a Pythagorean square figure worked in numbers
This folio sets out geometric constructions of the tangent and secant of a circle, annotated with the values 6 6 - 12 4, one figure noted as drawn inverted ('capovolto'). A further figure is described as analogous to, and as illustrating, the Pythagorean theorem, worked with the numbers 64, 36 and 100 (that is, 8-squared plus 6-squared equals 10-squared) and referred to 'the sixth' proposition. The compiler records three figures treating the same theme.
On this page
Tangent and secant of a circle
A construction of the tangent and secant lines to a circle, annotated with the values 6 6 - 12 4. One version of the figure is noted as drawn inverted (capovolto).
Pythagorean-theorem figure
A figure illustrating the Pythagorean theorem, presented as analogous to the tangent/secant construction. It is worked with the numbers 64, 36 and 100 (the squares 8-squared plus 6-squared equal 10-squared) and cites 'the sixth' proposition ('per la sesta').
Three figures on one theme
The compiler notes three figures treating the same geometric theme together on the sheet.