Books Books 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. A Course of Mathematics: For the Use of Academies as Well as Private Tuition ... - Page 292
by Charles Hutton - 1831 ## Mathematics, mechanics, heat

American School (Chicago, Ill.) - Engineering - 1903 - 392 pages
...Let ABCDEF oe the given polygon. To prove that the sum of the interior angles A, B, C, D, E, and F, is equal to twice as many right angles as the figure has sides minus two. If from any vertex as A, diagonals AC, AD, AE, are drawn, the polygon will be divided into... ## Interim Report of the Commissioners on Certain Parts of Primary Education ...

...prove that LP ie less than LM. 3. Prove that the sum of the interior angles of any rectilineal figure is equal to twice as many right angles as the figure has sides, dimished by four right angles. ABC is an equilateral triangle in which AD is drawn perpendicular to... ## Manual

1903
...1. Show that 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. A BCD is a quadrilateral figure, and the angles at A, B, C and D are bisected. Straight lines are drawn... ## A Treatise on Surveying, Volume 1

Reginald Empson Middleton - Surveying - 1904 - 332 pages
...close polygon, which may be summarised as follows. The sum of the ' interior ' angles augmented by four right angles is equal to twice as many right angles as the figure has sides. The sum of the ' exterior ' angles diminished by four right angles is equal to twice as many right... ## Introduction to Geometry: A Manual of Exercises for Beginners

William Schoch - Geometry - 1904 - 152 pages
...angles of a polygon without measuring them ? Exercise 33. If the sum of the interior angles of a polygon is equal to twice as many right angles as the figure has sides less four right angles, determine the sum of the interior angles of : 1. A six-sided polygon, or hexagon.... ## A Text-book of Euclid's Elements for the Use of Schools, Book 1

Euclid - Euclid's Elements - 1904 - 488 pages
...right angles as the figure has sides. But all the interior angles, with four right angles, are together equal to twice as many right angles as the figure has sides. I. 32, Cor. 1. Therefore all the interior angles, with all the exterior angles, are together equal... ## The Colliery Manager's Handbook

Caleb Pamely - 1904 - 1238 pages
...for, " The sum of all the interior angles of any rectilinear figure, together with 4 right angles, are equal to twice as many right angles as the figure has sides." This is not so thorough a test as the plotting, because it checks only the angles taken and not the... ## Catalogue ...

Yale University. Sheffield Scientific School - 1905 - 1074 pages
...altitude is 3 in. PLANE GEOMETRY SEPTEMBER, 1909 1. The sum of all the interior angles of any polygon is equal to twice as many right angles as the figure has sides, less four right angles. 2. The angle between two chords which intersect within a circle is measured... ## Annual Report of the Commissioners ..., Volume 70

1905 - 946 pages
...parallel to the base and half of it. D Papen. 6. The sum of all the interior angles of any polygon and four right angles is equal to twice as many right angles as there are eides to the polygon. 7. Find a point which shall be equally distant from the three angles... 