# Elements of Geometry: Containing the First Six Books of Euclid, with a Supplement on the Quadrature of the Circle and the Geometry of Solids : to which are Added Elements of Plane and Spherical Trigonometry

W.E. Dean, 1853 - 317 σεκΏδερ

### ‘ι κίμε οι ςώόστερ -”ΐμτανγ ξώιτιξόρ

Ρεμ εμτοπΏσαλε ξώιτιξίρ στιρ σθμόηειρ τοποηεσΏερ.

### Ργλοωικό αποσπήσλατα

”εκΏδα 49 - If a straight line be divided into two equal parts, and also into two unequal parts; the rectangle contained by the unequal parts, together with the square of the line between the points of section, is equal to the square of half the line.
”εκΏδα 72 - THE angles in the same segment of a circle are equal to one another...
”εκΏδα 35 - To a given straight line to apply a parallelogram, which shall be equal to a given triangle, and have one of its angles equal to a given rectilineal angle.
”εκΏδα 27 - Straight lines which are parallel to the same straight line are parallel to one another. Triangles and Rectilinear Figures. The sum of the angles of a triangle is equal to two right angles.
”εκΏδα 27 - To draw a straight line through a given point parallel to a given straight line. Let A be the given point, and BC the given straight line ; it is required to draw a straight line through EAF the point A, parallel to the straight line '
”εκΏδα 145 - If the vertical angle of a triangle be bisected by a straight line which also cute the base, the rectangle contained by the sides of the triangle is equal to the rectangle contained by the segments of the base, together with the square on the straight line which bisects the angle.
”εκΏδα 17 - The angles which one straight line makes with another upon one side of i't, are either two right angles, or are together eqval to two right angles.
”εκΏδα 132 - IF three straight lines be proportionals, the rectangle contained by the extremes is equal to the square of the mean : and if the rectangle contained by the extremes be equal to the square of the mean, the three straight lines are proportionals.
”εκΏδα 292 - All the interior angles of any rectilineal figure, together with four right angles, are equal to twice as many right angles as the figure has sides.
”εκΏδα 11 - BC. Wherefore from the given point A a straight line AL has been drawn equal to the given straight line BC.