Elements of Geometry and Conic Sections |
From inside the book
Results 1-5 of 39
Page 11
... parallelogram is that which has its op- posite sides parallel . A trapezoid is that which has only two sides parallel . 18. The diagonal of a figure is a line B which joins the vertices of two angles not adjacent to each other . Thus ...
... parallelogram is that which has its op- posite sides parallel . A trapezoid is that which has only two sides parallel . 18. The diagonal of a figure is a line B which joins the vertices of two angles not adjacent to each other . Thus ...
Page 32
... parallelogram are equal to each other . Let ABDC be a parallelogram ; then will its opposite sides and angles be equal to each other . · A B Draw the diagonal BC ; then , because AB is parallel to CD , and BC meets them , the alternate ...
... parallelogram are equal to each other . Let ABDC be a parallelogram ; then will its opposite sides and angles be equal to each other . · A B Draw the diagonal BC ; then , because AB is parallel to CD , and BC meets them , the alternate ...
Page 33
... parallelogram into two equal triangles . PROPOSITION XXX . THEOREM ( Converse of Prop . XXIX . ) . If the opposite sides of a quadrilateral are equal , each to each , the equal sides are parallel , and the figure is a parallelo gram ...
... parallelogram into two equal triangles . PROPOSITION XXX . THEOREM ( Converse of Prop . XXIX . ) . If the opposite sides of a quadrilateral are equal , each to each , the equal sides are parallel , and the figure is a parallelo gram ...
Page 34
... parallelogram . Therefore , if two op- posite sides , & c . PROPOSITION xxxii . THEOREM . The diagonals of every parallelogram bisect each other Let ABDC be a parallelogram whose di- agonals , AD , BC , intersect each other in E ; then ...
... parallelogram . Therefore , if two op- posite sides , & c . PROPOSITION xxxii . THEOREM . The diagonals of every parallelogram bisect each other Let ABDC be a parallelogram whose di- agonals , AD , BC , intersect each other in E ; then ...
Page 57
... altitude of a triangle is the perpen- dicular let fall from the vertex of an angle on the opposite side , taken as a base , or on the base produced . 7. The altitude of a parallelogram is the perpendicular drawn BOOK IV . 55 57 BOOK IV.
... altitude of a triangle is the perpen- dicular let fall from the vertex of an angle on the opposite side , taken as a base , or on the base produced . 7. The altitude of a parallelogram is the perpendicular drawn BOOK IV . 55 57 BOOK IV.
Other editions - View all
Common terms and phrases
ABCD AC is equal allel altitude angle ABC angle ACB angle BAC base BCDEF bisected chord circle circumference cone convex surface curve described diagonals diameter draw ellipse equal angles equal to AC equally distant equiangular equilateral equivalent exterior angle foci four right angles frustum given angle given point greater hyperbola hypothenuse inscribed intersect join latus rectum Let ABC lines AC Loomis major axis mean proportional measured by half meet number of sides ordinate parabola parallelogram parallelopiped pendicular perimeter perpen perpendicular plane MN prism Professor of Mathematics PROPOSITION pyramid radii radius ratio rectangle regular polygon right angles Prop Scholium segment side AC similar similar triangles slant height solid angle sphere spherical triangle square subtangent tangent THEOREM triangle ABC vertex vertices
Popular passages
Page 60 - Any two rectangles are to each other as the products of their bases by their altitudes.
Page 17 - If two triangles have two sides, and the included angle of the one, equal to two sides and the included angle of the other, each to each, the two triangles will be equal, their third sides will be equal, and their other angles will be equal, each to each.
Page 101 - When you have proved that the three angles of every triangle are equal to two right angles...
Page 63 - IF a straight line be divided into any two parts, the square of the whole line is equal to the squares of the two parts, together with twice the' rectangle contained by the parts.
Page 18 - BC common to the two triangles, which is adjacent to their equal angles ; therefore their other sides shall be equal, each to each, and the third angle of the one to the third angle of the other, (26.
Page 10 - When a straight line standing on another straight line makes the adjacent angles equal to one another, each of the angles is called a right angle ; and the straight line which stands on the other is called a perpendicular to it.
Page 32 - 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.
Page 37 - Proportional, when the ratio of the first to the second is equal to the ratio of the second to the third.
Page 15 - Wherefore, when a straight line, &c. QED PROP. XIV. THEOR. If, at a point in a straight line, two other straight lines, upon the opposite sides of it, make the adjacent angles together equal to two right angles, these two straight lines shall be in one and the same straight line.
Page 44 - A Circle is a plane figure bounded by a curved line every point of which is equally distant from a point within called the center.