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. Elements of Plane Geometry: For the Use of Schools - Page 81
by Nicholas Tillinghast - 1844 - 96 pages ## A Course of Mathematics: For the Use of Academies as Well as ..., Volume 1

Charles Hutton - Mathematics - 1812
...or intvard angles, as the figure has sides : therefore the sum of all the inward and outward angles, is equal to twice as many right angles as the figure has sides. But the sum of all the inward angles, with four right angles, is equal to twice as many right angles... ## A Course of Mathematics: In Two Volumes : for the Use of Academies, as Well ...

Charles Hutton - Mathematics - 1816
...former sum. Hence it follows thai the sum of .ill the inward angles of the polygon alone, A + B+C+D + E, is equal to twice as many right angles as the figure has skies, wanting the said four right angles, q. ED THEOREM XX. WHEN every Side of any Figure is produced... ## The Elements of Euclid: Viz. the First Six Books, Together with the Eleventh ...

Euclides - 1816 - 528 pages
...with four right angles. Therefore all the angles of the figure, together with four right angles, are equal to twice as many right angles as the figure has sides. Cor. 2. All the exterior angles of any rectilineal figure' are together equal to four right angles.... ## American Edition of the British Encyclopedia: Or, Dictionary of ..., Volume 6

...deduces from the same proposition, this theorem, viz. that the sum of the angles of every rectilinear figure is equal to twice as many right angles as the figure hath sides, excepting or subtracting four. INTERPOLATION, among critics, denotes a spurious passage,... ## Elements of Geometry: Containing the First Six Books of Euclid, with a ...

Euclid, John Playfair - Circle-squaring - 1819 - 348 pages
...all the angles of the figure, together with four right angles, that is, the angles of the figure are equal to twice as many right angles as the figure has sides, wanting four. COR. 2. All the exterior angles of any rectilineal figure are tegether equal to four... ## A Course of Mathematics: For the Use of Academies, as Well as Private ...

Charles Hutton - Mathematics - 1822 - 618 pages
...or inward angles, as the figure IMS sides : therefore the sum of all the inward and outward angles, is equal to twice as many right angles as the figure has sides. But the sum of all the inward angles, with four right angles, is equal to twice as many right angles... ## Euclid's Elements of Geometry: The Six First Books. To which are Added ...

Rev. John Allen - Astronomy - 1822 - 516 pages
...FC, FD, FE ; there are formed as many triangles as the figure has sides, all the angles of which are equal to twice as many right angles as the figure has sides [by this prop.] ; but of these all the angles about the point F are equal to four right angles [Ctor.... ## The First Six Books with Notes

Euclid - 1822 - 179 pages
...Cor. 6. All the internal angles of any rectilineal figure, ABCDE, together with four right angles, are equal to twice as many right angles as the figure has sides. Take any point F within the figure and draw the right lines FA, FB, FC, FD, and FE. There are formed... ## A treatise on navigation, and nautical astronomy

Edward Riddle - Nautical astronomy - 1824 - 572 pages
...angles as the figure has sides. But all the interior angles, and four right angles, are also together equal to twice as many right angles as the figure has sides, (Theo. 25.) Hence the interior and the exterior angles of the figure are, together, equal to the interior... 