Osgood, William F. (William Fogg), 1864-1943, Graustein, William C. (William Caspar), 1888-1941, joint author · New York : The Macmillan Company · leaf 371
ch is, say, 2units below the x-axis willslide a distance 2/c to theleft. In other words, thealgebraic distance throughwhich each line slides isequal to k times the algebraicdistance of the line from theic-axis. This is true, also, of themotion of each point of therectangle, since the lines slide as… … —X Fig. 14 (1) are the equations of the transformation. Thus far we have assumed that k is positive. It mayequally well be negative. Then points above the axis of x areshifted to the left, and points below it to the right. If the sliding were along parallels to the axis of y, the trans-formation…
