Page:First six books of the elements of Euclid 1847 Byrne.djvu/167

 BOOK IV. PROP. VIII. PROB. To inscribe a circle in a given square. Make..., and..., draw..., and... (B. I. pr. 31.) ...is a parallelogram; and since...(hyp.) ...is equilateral (B. i. pr. 34.) In like manner, it can be shown that... are equilateral parallelograms; ..., and therefore if a circle be described from the concourse of these lines with any one of them as radius, it will be inscribed in the given square. (B. 3. pr. 16.) Q.E.D.