Example.
Suppose ABC the triangle from which I would cut off one acre, that is to say 160 rodde by a paralele lyne to the side AB, first therefore I measure the Area of that whole triangle as was before taught in this boke, fynding AB 50 perch, AC 120, BC 130, and so consequentely the Area of that triangle 3000 rodde, the square of AC is 14400, the square of BC is 16900, these augmented by 160, bring 2304000, and 2704000, and these diuided by 3000, produce in the quotientes 768 and 901 ⅓, the roote of 768 perches) being 27 perches 12 foote) I mesure out in the side AC,
beginning from
C, admit it ende at
D, likewise the roote of
901 ⅓ perches is
30 pear∣ches, and betwene
4 and
9 in∣ches, measuring therefore
30 perches from
C in the other side
CB I sette vp a marke at
E. Nowe if you drawe a streyght lyne from
D to
E it shall be a paralele to
AB, and the peece of grounde, represented by
DEC, an exacte acre. But if you desire to laye oute this acre at one of the sides as ye may see in the figure signified by the quadrilater Superficies
ABGF, Then must ye deducte the aforesayde
160 roddes fro the Area of that triangle, the re∣mayne is
2840, whiche I multiplye as before in the square of
AC, so haue I
40896000, Lykewise the same 2840 augmented by the square of
BC produ∣ceth
48016000, these products seuerally deuided by
3000, the Area of the whole triangle will yelde in the quotientes
13632 and
16005 ⅓ theyr quadrate rootes are
116 perches
12 ½ foote, the length of the lyne
CF, and
126 perches
8 ½ foote, the lyne
GC, Or if yee deducte those rootes from the whole sides
AC, and
BC there wil remayn
3 rodde
4 foote from
A to
F, and
3 rodde
8 foote from
B to
G And thus may you in all Triangular peeces of ground, exactly lay forth an acre,