78 Mr. glenie’s Proportions . 
rectangle ab, as; that is, the proportion of ad to ab (i. 
E. 6.) is equal to the proportion of the fquare on ac to 
the redangle al, as (16, E. 5.) But ad hath to ac the 
proportion of ac to ap (cor. 3. to prop. 1.). Therefore, 
the redangle ad, ac, hath to the fquare on ac the propor- 
tion of the redangle ac, as, to the redangle ap, as (i. 
E. 6.). Therefore ad hath to as or ab the proportion of 
the fquare on ac to the redangle ap, as (16. E. 5. and 
1. E. 6.). Hence the redangle al, as, is equal to the 
redangle ap, as (1 1 . and 1 6 . E. 5.), and al, ap, are con- 
fequently equal. But as al to ap, fo is bl to BQ_(by cor. 
5. prop. 1.). Therefore bl, bq^, are Ukewife equal*. 
\ 
PRO* 
