Books Books
... the three angles of a triangle are together equal to two right angles, although it is not known to all.
The Works of John Playfair ...: With a Memoir of the Author ... - Page 335
by John Playfair - 1822

## The Elements of Euclid for the Use of Schools and Colleges: Comprising the ...

Euclid, Isaac Todhunter - 1867 - 426 pages
...equilateral ; therefore the three angles EGD, GDE, DEG are equal to one another. [I. 5. Corollary. But the three angles of a triangle are together equal to two right angles ; [I. 32. therefore the angle EGD is the third part of two right angles. In the same manner it may...

## A Dictionary of Science, Literature, & Art: Comprising the ..., Volume 1

George William Cox - 1867 - 1002 pages
...considered generally, and without restriction to any individual magnitude, Thus, the proposition that the three angles of a triangle are together equal to two right angles, is an abstract truth, applying equally to all triangles whatsoever. Abstract Mathematics is opposed...

## Henry's junior dictation lessons

Joseph Fernandez - 1868 - 188 pages
...at drill, or on parade. The angels, in great hosts, were with the shepherds, at our Saviour's birth. The three angles of a triangle are together equal to two right angles. The smugglers cast overboard nine ankers of brandy, and fastened them to the anchor of the ship. On antique...

## School Atlas of Astronomy: Comprising, in Twenty-one Plates, a Complete ...

Alexander Keith Johnston - 1869 - 172 pages
...of OA, which represents the distance of the object from the original station A. Since in all cases the three angles of a triangle are together equal to two right angles, and since the angles A, B, at the base of the triangle OAB are known by measurement, it necessarily...

## Civil service guide

Robert Johnston (F.R.G.S.) - 1869 - 196 pages
...meant by a corollary ? State and prove the corollaries to the proposition in which it is proved that the three angles of a triangle are together equal to two right angles. 4. If a straight line be divided into any two parts, the square of the whole line is equal to the squares...

## The amateur mechanic's workshop, by the author of The lathe and its uses

James Lukin - 1870 - 174 pages
...C and D are each 45° (half the right angles at the corners of the square), then if it is true that the three angles of a triangle are together equal to two right angles, the angle at E must be a right angle (for we have taken from the triangle the two angles G and D, each...

## An Essay in Aid of a Grammar of Assent

John Henry Newman - 1870 - 500 pages
...cannot conceive a man having before him the series of conditions and truths on which it depends that the three angles of a triangle are together equal to two right angles, and yet not assenting to that proposition. Were all propositions as plain, though assent would not...

## The Amateur Mechanic's Workshop: a Treatise Containing Plain and Concise ...

James Lukin - 1874 - 214 pages
...C and D are each 45° (half the right angles at the corners of the square), then if it is true that the three angles of a triangle are together equal to two right angles, the angle at E must be a right angle (for we have taken from the triangle the two angles G and D, each...