Books Books Straight lines which are parallel to the same straight line are parallel to one another. Mathematics in the Lower and Middle Commercial and Industrial Schools of ... - Page 17
by Edson Homer Taylor - 1915 - 96 pages ## Philosophical Remains of George Croom Robertson: With a Memoir

George Croom Robertson - Philosophy - 1894 - 520 pages
...contrapositive the passage from (2) to (1). It is there said that Theorem 24, " Straight lines that are parallel to the same straight line are parallel to one another," is the contrapoeitive of Axiom 5 (p. 15)— "Two straight lines that intersect one another cannot both... ## Philosophical Remains of George Croom Robertson: With a Memoir

George Croom Robertson - Philosophy - 1894 - 522 pages
...contrapositive the passage from (2) to (1). It is there said that Theorem 24, "Straight lines that are parallel to the same straight line are parallel to one another," is the contrapositive of Axiom 5 (p. 15)— "Two straight lines that intersect one another cannot both... ## Mathematics: Mechanic's bids and estimates. Mensuration for beginners. Easy ...

Seymour Eaton - 1899 - 362 pages
...perpendicular lines drawn to parallel lines are themselves parallel. Lesson No. 15 PROPOSITION 30. THEOREM Straight lines which are parallel to the same straight line are parallel to each other. Let AB and CD be each of them parallel to EF; then AB shall be parallel to CD. Proof: Because... ## Plane and Solid Geometry

William James Milne - Geometry - 1899 - 398 pages
...the given line. In what direction do these two lines extend with reference to each other? Theorem. Straight lines which are parallel to the same straight line are parallel to each other. ' Data: Any straight lines, as AB A (75 B and CD, each parallel to another c /' D straight... ## Plane Geometry

William James Milne - Geometry, Modern - 1899 - 258 pages
...the given line. In what direction do these two lines extend with reference to each other ? Theorem. Straight lines which are parallel to the same straight line are parallel to each other. Data: Any straight lines, as AB A and CD, each parallel to another c straight line, as... ## A Text-book of Euclid's Elements for the Use of Schools. Books I and II, Book 1

Henry Sinclair Hall, Frederick Haller Stevens - Euclid's Elements - 1900 - 330 pages
...Propositions, dealing with parallel straight lines, depends on Axiom 12 ? Furnish an alternative proof. 3. Straight lines which are parallel to the same straight line are parallel to one another [Prop. 30]. Deduce this from Playfair's Axiom. 4. Define a parallelogram, an altitude of a triangle,... ## The School World, Volume 3

Education - 1901 - 548 pages
...angle and name the different kinds of angles. Describe an ancle equal to a givtn angle. (4) S' might lines which are parallel to the same straight line are parallel to one another. Two straight lines are drawn parallel to the base of an isosceles triangle ; show that the segments... ## The School World: A Monthly Magazine of Educational Work and Progress, Volume 5

Education - 1903 - 692 pages
...of interior angles on the same side of the cutting are together equal to two right angles, dwi the two straight lines are parallel ; and the converse....lines which are parallel to the same straight line «« parallel to one another. Triangles and Rectilinear Figures. — The sum of the angles of > triangle... ## Elementary Geometry: Practical and Theoretical

Charles Godfrey, Arthur Warry Siddons - Geometry - 1903 - 384 pages
...are acute. (iii) London Bridge is a stone bridge. (iv) A nigger is a man with woolly hair. THEOREM 6. Straight lines which are parallel to the same straight line are parallel to one another. ~T fig. 89. Data AB, CD are each || to XY. To prove that AB is || to CD. Construction Draw a st. line... 