**TI83F* AppVariable file 12/24/08, 18:40D 3 GLGE073 1 nav 9AE51D1EC13445C5B24A00CF0B737DCFGLGE07.'GLGE071  center of dilation Hcenter of dilation:ÖThe center point from which dilations are performed. cross products¨cross products:ÖThe product of the terms on the diagonals when two ratios are compared.ÖExample: In the proportion 2/3 = 8/12 the cross products are 2 12 and 3 8.  dilation dilation:ÖA transformation determined by a center point C and a scale factor k. When k > 0, the image P' of P is the point on vector CP such that ÖCP'= |k| CP. When k < 0, the image P' of P is the point on the ray opposite vector CP such that ÖCP' = k CP.  enlargement >enlargement:ÖAn image that is larger than the original figure. extended ratios Jextended ratios:ÖRatios that are used to compare three or more quantities. extremesAextremes:ÖIn the proportion Öa/b = c/d, a and d are the extremes. means;means:ÖIn the proportion Öa/b = c/d, b and c are the means. midsegment of a triangleemidsegment of a triangle:ÖA segment with endpoints that are the midpoints of two sides of a triangle.   proportionUproportion:ÖAn equation of the form a/b = c/d stating that two ratios are equivalent.  ratio/ratio:ÖA comparison of two numbers by division.   reduction =reduction:ÖAn image that is smaller than the original figure.  scale Vscale:ÖA ratio or rate between the actual size of an object and the size of its model.  scale drawing `scale drawing:ÖA drawing that is similar to an actual object, but is either enlarged or reduced.  scale factor:scale factor:ÖA scale written as a ratio in simplest form. scale factor of a dilation hscale factor of a dilation:ÖThe ratio of a length on an image to a corresponding length on the preimage.  scale model gscale model:ÖA replica of an original object that is too large or too small to be built at actual size. similar polygons “similar polygons:ÖTwo polygons are similar if and only if their corresponding angles are congruent and corresponding side lengths are proportional. similarity transformation Ssimilarity transformation:ÖWhen a figure and its transformation image are similar. similarity ratio @similarity ratio:ÖThe scale factor between two similar polygons.¦