There was a problem when proofreading this page.
BOOK I. PROP. XLII. THEOR.
43
 | An image should appear at this position in the text. To use the entire page scan as a placeholder, edit this page and replace "{{missing image}}" with "{{raw image|First six books of the elements of Euclid 1847 Byrne.djvu/77}}". Otherwise, if you are able to provide the image then please do so. For guidance, see Wikisource:Image guidelines and Help:Adding images. |  |
O construct a parallelogram equal to a given triangle and having an angle equal to a given rectilinear angle .
Make = (pr. 10.)
Draw .
Make = (pr. 23.)
Draw (pr. 31.)
= twice (pr. 41.)
but = (pr. 38.)
∴ = .
Q. E. D.
