| Edward Wells - Arithmetic - 1723 - 294 pages
...the Sum of all the Angles in all the Tri~ angles, into which the Figure is divided, will together be **equal to twice as ma-ny right Angles, as the Figure has Sides.** But the Angles about P, the inward Point of each Figure, wherein all the Triangles concur, are (by... | |
| Thomas Malton - 1774 - 482 pages
...the Sides. ie equal to four Right Angles. And, all the internal Angles of any Right-lined Figure are **equal to twice as many Right Angles as the Figure has Sides,** wanting four, (Th. i. i0. i.) confequently, the external Angles being equal to thofe four (Th. 2. of... | |
| John McGregor (teacher of mathematics.) - Mathematics - 1792 - 431 pages
...been accurately taken, adá all the inward angles into one fum ; and when the work is right, their fum **is equal to twice as many right angles as the figure has** fides, wanting 4 right angles, (Euclid 31.1. Cor. 1.) Or, inftead of the inward angles, their füpplements... | |
| Mathematics - 1801 - 658 pages
...;• add all the inward angles A, B, C, &c. together, and when the work is right, their sum will be **equal to twice as many right angles, as the figure has sides,** wanting four right angles. And when there is an angle, as F, that bends inward, and you measure the... | |
| John Playfair - Euclid's Elements - 1806 - 320 pages
...if a side of a triangle, &c. QED "7^ COR. 1. All the interior angles of any rectilineal figure are **equal to twice as many right angles as the figure has sides,** wanting four right angles. For any rectilineal figure ABCDE can be divided into as many triangles as... | |
| Robert Simson - Trigonometry - 1806 - 518 pages
...D, CoR. 1 . 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.** For any rectilineal figure ABCDE can be divided into as many triangles as the figure has sides, by... | |
| Charles Hutton - Mathematics - 1807
...work ; add all the inward angles A, B, c, &c, together ; for when the work is right, their sum will ba **equal to twice as many right angles as the figure has sides,** wanting 4 right angles. But when there is an angle, as F, that bends inwards, and you measure the external... | |
| Sir John Leslie - Geometry, Plane - 1809 - 522 pages
...is equal to two right angles. All the exterior angles therefore, added to the interior angles, ftre **equal to twice as many right angles as the figure has sides.** Consequently the exterior angles are equal to the four right angles which, by the last Proposition,... | |
| John Dougall - 1810 - 554 pages
...each is one third part of two right angles, or two thirds of one right angle. PROP. VIII. fig. 21. **The sum of all the interior angles of a polygon is equal to twice as many right angles,** wanting four, as the figure has sides. Let the figure ABCDEF, be a polygon of six sides, that is, a... | |
| Charles Hutton - Mathematics - 1811
...triangles, is equal to two right angles (th. 17); therefore the sum of the angles of all the triangles **is equal to twice as many right angles as the figure has sides.** But the sum of all the angles about the point P, which are so many many of the angles of the triangles,... | |
| |