RELFE BROTHERS' EUCLID SHEETS. PROPOSITIONS 1–26, BOOK 1, ARE NOW PUBLISHED IN A SIMILAR FORM TO THIS. PROPOSITION III. From the greater of two given straight lines to cut off a part equal to the less. is the greater. Let and be the two given straight lines, of which the less. From the point draw the straight line at the equal to ; and from the center cutting in the point Then distance describe the circle shall off, equal to the less. RELFE BROTHERS, 6, CHARTERHOUSE BUILDINGS, LONDON, E.C. PROPOSITIONS 1—26, BOOK I, ARE NOW PUBLISHED IN A SIMILAR FORM TO THIS. PROPOSITION I. To describe an equilateral triangle upon a given finite straight line. From the center at the distance describe the circle ; from the center ; and at the distance describe the circle ; and from one of the points in which the circles cut one another, draw the straight lines to the points Then shall be an equilateral triangle. Because the point is the center of the circle therefore is equal to because the point is the center of the circle therefore is equal to it has been proved that is equal to ; therefore are each of them equal to ; but things which are equal to the same thing are equal to one another; therefore is equal to ; wherefore are equal to one another : and the triangle is therefore equilateral, and it is described upon the given straight line ; but RELFE BROTHERS, 6, CHARTERHOUSE BUILDINGS, LONDON, E.C. |