 | John Love - 1720 - 290 ページ
...fo great as 90 Degrees ; or which confifts of two Acute Angles and one Obtufe •viz. at that D. 3. All the three Angles of any Triangle are equal to two Right Angles, or 1 80 Degrees $ k> that one Angle being known, the other two together are known a lib; or two being... | |
 | John Leng (bp. of Norwich.) - 1730 - 536 ページ
...Mathematicks, upon viewing a great variety of Triangles and other figures, fhould take a fancy to deny that the three angles of any triangle are equal to two right angles, or to the three angles of any other triangle}beca.ufe he will not give himfelf the trouble of confidering... | |
 | John Love - 1744 - 288 ページ
...great as 90 Degrees; or which confifts of two Af cute Angles and one Obtufe, viz. as that D» , 5. All the three Angles of any Triangle are equal to two Right Angles, or .., 1 80 Degrees ; fci that One Angle being known, tne other two together are known alfo ; or two.be1hg... | |
 | John Keill - 1772 - 462 ページ
...I fay, two oppofite Angles thereof are equal to two Right Angles. For join AD, BC. \ Then, becaufe the three Angles of any Triangle are * equal to two Right Angles, the three Angles of the* 3Z- Tt Triangle ABC, viz. the Angles CAB, ABC, BCA, are equal to two Right... | |
 | John Keill - 1782 - 476 ページ
...D. I fay, two oppofite Angles thereof are equal to two Right Angles. F»rjoin AD, B C. Then, becaufe the three Angles of any Triangle are * equal to two Right Angles, the three Angles of the * aZl '• Triangle ABC, viz. the Angles CAB, ABC, BC A, are equal to-two Right... | |
 | John Love - 1792 - 288 ページ
...as 90 degrees ; or as C, which con'f1fts of two acute angles and one obt1ife, viz, that at "d.> 3. All the three angles of any triangle are equal to two 'right angles, or 180 degrees; fo that one angle being known, the fiirri of the other two becomes known alfo ., or... | |
 | Charles Butler - 1814 - 582 ページ
...rad.— log. AB ; whence the angle B is found, both by natural numbers and logarithms. Lastly, since the three angles of any triangle are equal to two right angles (32. 1.) =180", and the angle C (a right angle) = 90", v B+A= (180>-C=lS<r— 90°=) 90°; but the... | |
 | John Playfair - 1819 - 354 ページ
...each to each, the third angles are also equal. Now, this being demonstrated, it is easy to prove that the three angles of any triangle are equal to two right angles. Let ABC be a triangle right angled at A, draw AD perpendicular to BC. The triangles ABD, ABC have the... | |
 | John Radford Young - 1827 - 228 ページ
...Therefore the three angles of a triangle cannot be greater than two right angles. PROPOSITION III. The three angles of any triangle are equal to two right angles. If what is affirmed be not true, let the three angles of the triangle ACB be less than two right angles,... | |
 | 1840 - 526 ページ
...we liavc no doubt whatever that in respect to the theory of parallels it U no amendment of Euclid. = ABD. Similarly DCB = CAB; whence the angles at A and...all the three angles of any triangle are equal to l\vo right angles. It is not our intention to go fully into the objections which have been made to... | |
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We wish to prove that The three angles of any triangle are equal to two right angles. Let... 
