 | Euclides - 1855 - 230 pages
...quadrilateral ABHG is similar and similarly situated to the quadrilateral CDEF. DEMONSTRATION. Because the angle A is equal to the angle C, and the angle ABG to CDF, therefore the remaining angle AGB is equal to the remaining angle CFD (b), wherefore the... | |
 | Eucleides - 1860 - 396 pages
...quadrilateral ABIIG is similar and similarly situated to the quadrilateral CDEF. DEMONSTRATION. Because the angle A is equal to the angle C, and the angle ABG to CDF, therefore the remaining angle AGB is equal to the remaining angle CFD (b), wherefore the... | |
 | L J V. Gerard - 1874 - 428 pages
...the opposite angles are equal to each other, is a parallelogram. Let ABCD be a quadrangle of which the angle A is equal to the angle C, and the angle B equal to the angle D. Because the angles A and B are respectively equal to the angles C and D, the... | |
 | Euclid, James Bryce, David Munn (F.R.S.E.) - Geometry - 1874 - 236 pages
...are equal. Let ABCD be a four-sided figure; it is required to prove that it is a parallelogram, 1. If the angle A is equal to the angle C, and the angle B equal to the angle i), Since all the angles of the figure taken together make four right angles (I.... | |
 | Isaac Todhunter - Euclid's Elements - 1880 - 208 pages
...27. Similarly it may be shewn that AD is parallel to BC. 77. Let ABCD be a quadrilateral such that the angle A is equal to the angle C, and the angle B equal to the angle D : then the figure shall be a parallelogram. The angle A is equal to the angle... | |
 | Thomas Franklin Holgate - Geometry - 1901 - 462 pages
...ABCD be a parallelogram It is required to prove that AB is equal to DC and AD equal to BC; also that the angle A is equal to the angle C, and the angle B equal to the angle D. Proof. Join a pair of opposite vertices A and C. Because AB is parallel to... | |
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Because the angle A is equal to the angle C, and the angle... 