Books Books From this it is manifest, that if one angle of a triangle be equal to the other two, it is a right angle, because the angle adjacent to it is equal to the same two; and when the adjacent angles are equal, they are right angles. A Royal Road to Geometry: Or, an Easy and Familiar Introduction to the ... - Page 178
by Thomas Malton - 1774 - 440 pages ## Elements of Geometry: Containing the First Six Books of Euclid, with a ...

Euclid, John Playfair - Circle-squaring - 1819 - 348 pages
...greater than a right angle. Therefore, in a circle, &c. Q,. ED COR. From this it is manifest, that if one angle of a triangle be equal to the other two, it is a right angle, because the angle adjacent to it is equal to the same two ; and when the adjacent angles are equal,... ## Elements of Arithmetic, Algebra, and Geometry

George Lees - 1826 - 266 pages
...right angle. Therefore, in a circle, &c. QED *- .1 . » • N Cor. From this, it is manifest, that if one angle of a triangle be equal to the other two, it is a right angle, because the angle adjacent to it is equal to the same two ; and, when Book l1. the adjacent angles... ## The Elements of Euclid: The Errors by which Theon, Or Others, Have Long ...

Robert Simson - Trigonometry - 1827 - 513 pages
...angle of the less segment is said to be less, than a right angle." COR. From this it is manifest, that if one angle of a triangle be equal to the other two, it is a right angle: because the angle adjacent to it is equal f to the same two ; and when the adjacent angles are equal,... ## The Elements of Euclid: Viz. the First Six Books, Together with the Eleventh ...

Euclid - 1835 - 540 pages
...angle of the ' less segment is said to be less than a right angle.' Con. From this it is manifest, that if one angle of a triangle be equal to the other two, it is a right angle, because the angle adjacent to it is equal to the same two ; and when the adjacent angles are equal,... ## The Teacher's Assistant in the "Course of Mathematics Adapted to the Method ...

Mathematics - 1836 - 472 pages
...a segment less than a simicircle is greater than a right angle. Cor. From this it is manifest, that if one angle of a triangle be equal to the other two, it is a right angle, because the angle adjacent to it is equal to the same two ; and when the adjacent angles are equal,... ## The First Six and the Eleventh and Twelfth Books of Euclid's Elements: With ...

Euclid - Geometry - 1837 - 410 pages
...3. If a triangle have a right angle, the remaining angles. are together equal to a right angle ; and if one angle of a triangle be equal to the other two, it is a right angle. Cor. 4. The angles at the base of a right-angled isosceles triangle are each half a right angle. Cor.... ## Elements of Plane Geometry According to Euclid

Andrew Bell - Euclid's Elements - 1837 - 240 pages
...angle ; wherefore the other ADC is greater than a right angle. COB. — From this it is manifest, that if one angle of a triangle be equal to the other two, it is a right angle, because the angle adjacent to it is equal to the same two ; and when the adjacent angles are equal,... ## Elements of Geometry: Containing the First Six Books of Euclid : with a ...

John Playfair - Geometry - 1837 - 332 pages
...angle ; wherefore the other ADC is greater than a right angle. COR. From this it is manifest, that if one angle of a triangle be equal to the other two, it is a right angle, because the angle adjacent to it is equal to the same two ; and when the adjacent angles are equal,... ## A complete treatise on Practical Land-Surveying, etc

Thomas Holliday - Surveying - 1838 - 404 pages
...8, plate I. Note 1. K—L is called the base, L—M the perpendicular, and K—M the hypothenuse. 2. If one angle of a triangle be equal to the other two, the figure is a rightangled triangle. 3. The squares of K—L and L—M are equal to the square of... 