| Elias Loomis - Conic sections - 1880 - 452 pages
...other. PROPOSITION XXVIII. THEOREM. All the interior angles of a polygon, together with four right **angles, are equal to twice as many right angles as the figure** IMS sides. Let ABCDE be any polygon ; then all its interior angles A, B, C, D, E, together with four... | |
| William Frothingham Bradbury - Geometry - 1880 - 260 pages
...minus two. Let ABCDEF be the given polygon ; the sum of all the interior angles A, B, C, D, E, F, is **equal to twice as many right angles as the figure has sides** minus two. For if from any vertex A, diagonals AC, AD, AE, are drawn, the polygon will be divided into... | |
| John Gibson - 1881 - 302 pages
...side opposite to it. 3. 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.** 4. Describe a parallelogram that shall be equal to a given triangle BCD, and have one of its angles... | |
| Thomas Holloway (surveyor.) - 1881 - 132 pages
...hundred and sixty degrees. 3. 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.** Although further systems of proof could easily be quoted, I consider the foregoing quite sufficient... | |
| Thomas Newton Andrews - Geometry - 1881 - 168 pages
...xxxi11., it is proved 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."** If we have to describe a pentagon on the base AB, we must first calculate the angles at the base. Thus... | |
| 1882 - 486 pages
...proposition it is shown that all the internal angles of any rectilineal figure, together with four right **angles, are equal to twice as many right angles as the figure has sides** ; also, that all the external angles of any rectilineal figure formed by producing the sides in the... | |
| College of preceptors - 1882 - 528 pages
...one is referred to. 5. 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.** 6. The opposite sides and angles of a parallelogram are equal ; and the diameter bisects the parallelogram.... | |
| Education, Higher - 1882 - 498 pages
...equal in every respect. 4 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.** 5. Equal triangles upon equal bases in the same straight line and towards the same parts are between... | |
| 1882 - 376 pages
...right angles; and that all the interior angles of any rectilineal n'gure, together with four right **angles, are equal to twice as many right angles as the figure has sides.** 3. If the square described upon one of the sides of a triangle is equal to the squares described upon... | |
| Marianne Nops - 1882 - 278 pages
...of a right angle or 60°. III. All the interior angles of any rectilineal figure added to four right **angles are equal to twice as many right angles as the figure has sides.** Now, any figure can be divided into as many triangles as it has sides by drawing lines from each of... | |
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