RELFE BROTHERS' EUCLID SHEETS.

PROPOSITIONS 1–26, BOOK I, ARE NOW PUBLISHED IN A SIMILAR FORM TO THIS.

PROPOSITION XVIII.

The greater side of every triangle is opposite to the greater angle.

RELFE BROTHERS' EUCLID SHEETS.

.

PROPOSITIONS 1–26, BOOK I, ARE NOW PUBLISHED IN A SIMILAR FORM TO THIS.

PROPOSITION XVII.

Any two angles of a triangle are together less than two right angles.

Let

be any triangle.

Then any two of its angles together shall be less than two right angles.

In like manner it may be demonstrated, that the angles

are less than

two right angles, as also the angles

Therefore any two angles of a triangle, &c.