Search results
Results From The WOW.Com Content Network
The nine-point circles are all congruent with a radius of half that of the cyclic quadrilateral's circumcircle. The nine-point circles form a set of four Johnson circles. Consequently, the four nine-point centers are cyclic and lie on a circle congruent to the four nine-point circles that is centered at the anticenter of the cyclic quadrilateral.
In the Class 7 textbook topic titled “Our Pasts-2”, pages 48 and 49 have been excluded. These pages mentioned “Mughal Emperors: Major campaigns and events.” The deletions also affected Biology and Chemistry textbooks as the theory of evolution and the periodic table were also purged from class 10 NCERT textbooks. [35] [36]
Similar figures. In Euclidean geometry, two objects are similar if they have the same shape, or if one has the same shape as the mirror image of the other.More precisely, one can be obtained from the other by uniformly scaling (enlarging or reducing), possibly with additional translation, rotation and reflection.
Two circles are congruent if they have the same diameter. In this sense, the sentence "two plane figures are congruent" implies that their corresponding characteristics are congruent (or equal ) including not just their corresponding sides and angles, but also their corresponding diagonals, perimeters, and areas.
Digital textbooks may also be known as e-textbooks or e-texts. Digital textbooks are a major component of technology-based education reform. They may serve as the texts for a traditional face-to-face class, an online course or degree, or massive open online courses (MOOCs). As with physical textbooks, digital textbooks can be either rented for ...
For three circles denoted by C 1, C 2, and C 3, there are three pairs of circles (C 1 C 2, C 2 C 3, and C 1 C 3). Since each pair of circles has two homothetic centers, there are six homothetic centers altogether. Gaspard Monge showed in the early 19th century that these six points lie on four lines, each line having three collinear points.
The two given circles α and β touch the n circles of the Steiner chain, but each circle C k of a Steiner chain touches only four circles: α, β, and its two neighbors, C k−1 and C k+1. By default, Steiner chains are assumed to be closed , i.e., the first and last circles are tangent to one another.
In the same year, the puzzle also appeared in A. Cyril Pearson's puzzle book. It was there named a charming puzzle and involved nine dots. [5] [2] Both versions of the puzzle thereafter appeared in newspapers. From at least 1908, Loyd's egg-version ran as advertising for Elgin Creamery Co in Washington, DC., renamed to The Elgin Creamery Egg ...