T. Sundara Row's Geometric exercises in paper folding; (1901)
Sundara Rao, T. (Tandalam), b. 1853 · Chicago, The Open court pub. company; [etc., etc.] · leaf 24
IN PAPER FOLDING 5 opposite corners B, D, is a diagonal of the square. One other diagonal is obtained by folding the square through the other pair of corners as in Fig. 5 n. We see that the diagonals are at right angles to each other, and that they bisect each other. 12. The point of intersection… … Fig. 6. 13. Each diagonal divides the square into two con- gruent right-angled isosceles triangles, whose vertices are at opposite corners. 14. The two diagonals together divide the square into four congruent right-angled isosceles triangles, whose vertices are at the center of the square.
Geometry -- Study and teaching · Paper work
Internet Archive · University of California Libraries · Public domain (published before 1931). Free to use for anything.
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