Books Books 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. A course of geometrical drawing - Page 2
by William Schofield Binns - 1861 ## Elements of Geometry: Containing the First Six Books of Euclid, with a ...

John Playfair - Euclid's Elements - 1806 - 320 pages
...angle at a point, it may be expressed ' by a letter placed at that point ; as the angle at E.' VII. When a straight line standing on another straight...stands on the other is called a perpendicular to it. _____ VIII, Book I. An obtuse angle is that which is greater than a right angle. IX. An acute angle... ## The Elements of Euclid: The Errors, by which Theon, Or Others, Have Long Ago ...

Robert Simson - Trigonometry - 1806 - 546 pages
...placed at that point; as < the angle at E.' X. When a straight line standing on another straight lii>e makes the adjacent angles equal to one another, each...stands on the other is called a perpendicular to it. XI. An obtuse angle is that which is greater than a right angle. XII. An acute angle is that which... ## Pantologia. A new (cabinet) cyclopædia, by J.M. Good, O. Gregory ..., Volume 5

John Mason Good - 1813 - 722 pages
...of two straight lines to or.e another, which meet together, but are not in the same straight line. 10. When a straight line standing on another straight...stands on the other is called a perpendicular to it. 11. An obtuse an¿le is that which is greater 'than a right angle. IS. An acnte angle is that which... ## The Elements of Euclid; viz. the first six books, together with the eleventh ...

Euclides - 1814 - 558 pages
...one angle at a point, it may be ex' pressed by a letter placed at that point; as the angle at E.' X. When a straight line standing on another straight...stands on the other is called a perpendicular to it. XI. An obtuse angle is that which is greater than a right angle. XII. An acute angle is that which... ## Elements of Geometry: Containing the First Six Books of Euclid: With a ...

John Playfair - 1819 - 354 pages
...one angle at a point, it may be expressed by a letter placed at that point ; as the angle at E.' VII. When a straight line standing on another straight...stands on the other is called a perpendicular to it. VIII. An obtuse angle is that which is greater than a right angle. An acute angle is that which is... ## Pantologia. A new (cabinet) cyclopædia, by J.M. Good, O. Gregory ..., Volume 5

John Mason Good - 1819 - 740 pages
...adjacent angles equal to one another, each of (lie angles is called и right angle; and the ira glu line which stands on the other is called a perpendicular to it. 11. An obtuse angle is that which is g cater than a right an^le. 12. Ли acute angle is that which... ## The Elements of Euclid: Viz. the First Six Books, Together with the Eleventh ...

Euclid, Robert Simson - Geometry - 1821 - 514 pages
...angle at ' a point, it may be expressed by the letter placed at that point; ' as the angle at E.' X. When a straight line standing on another straight...which stands on the other is called a perpendicular to „« —__ it. XI. An obtuse angle is that which is greater than a right angle. XII. An acute angle... ## A Popular Course of Pure and Mixed Mathematics ...: With Tables of ...

Peter Nicholson - Mathematics - 1825 - 1046 pages
...only one angle at a point, it may be expressed by a letter placed at that point ; as the angle at E.' 10. When a straight line standing on another straight...stands on the other is called a perpendicular to it. 11. An obtuse angle is that which is greater than a right angle. ^ 12. An acute angle is that which... ## Elements of Arithmetic, Algebra, and Geometry

George Lees - 1826 - 266 pages
...When a straight line AB, standing on another straight line CD, makes the adjacent angles ABC and ABD equal to one another, each of the angles is called...stands on the other, is called a perpendicular to it. •D OF GEOMETRY. with another CD, upon one side of it, are eitlier two right angles, or are, together,... 