t be inclosed with like sides.

_Example._

[Illustration]

This triangle A.B.C. hath ij. sides (that is to say) C.A. and
C.B, equal to ij. sides of the other triangle F.G.H, for A.C. is
equall to F.G, and B.C. is equall to G.H. And also the angle C.
contayned beetweene F.G, and G.H, for both of them answere to
the eight parte of a circle. Therfore doth it remayne that A.B.
whiche is the thirde lyne in the firste triangle, doth agre in
lengthe with F.H, w^{ch} is the third line in y^e second triangle
& y^e hole triangle. A.B.C. must nedes be equal to y^e hole
triangle F.G.H. And euery corner equall to his match, that is to
say, A. equall to F, B. to H, and C. to G, for those bee called
match corners, which are inclosed with like sides, other els do
lye against like sides.

_The second Theoreme._

In twileke triangles the ij. corners that be about the ground
line, are equal togither. And if the sides that be equal, be
drawen out in length then wil the corners that are vnder the
ground line, be equal also togither.

_Example_

[Illustration]

A.B.C. is a twileke triangle, for the one side A.C, is equal to
the other side B.C. And therfore I saye that the inner corners
A. and B, which are about the ground lines, (that is A.B.) be
equall togither. And farther if C.A. and C.B. bee drawen forthe
vnto D. and E. as you se that I haue drawen them, then saye I
that the two vtter angles vnder A. and B, are equal also
togither: as the theorem said. The profe wherof, as of al the
rest, shal apeare in Euclide, whome I intende to set foorth in
english with sondry new additions, if I may perceaue that it
wilbe thankfully taken.

_The thirde Theoreme._

If in annye triangle there bee twoo angles equall togither,
then shall the sides, that lie against those angles, be
equal also.

[Illustration]

_Example._

This triangle A.B.C. hath two corners equal eche to other, that
is A. and B, as I do by supposition limite, wherfore it foloweth
that the side A.C, is equal to that other side B.C, for the side
A.C, lieth againste the angle B, and the side B.C, lieth against
the angle A.

_The fourth Theoreme._

When two lines are drawen from the endes of anie one line,
and meet in anie pointe, it is not possible to draw two
other lines of like lengthe ech to his match that shal begin
at the same pointes, and end in anie other pointe then the
twoo first did.

_Example._

[Illustration