2,4,5+Similar+Figures

In order to understand the concept of similarity of triangles, one must think of two different concepts. On the one hand there is the concept of shape and on the other hand there is the concept of scale. If you were to draw a map, you would probably try to preserve the shape of what you are mapping, while you would make your picture at a scale, that is in proportion, to the original size. **
 * Two geometrical objects are called similar if they both have the same shape. More precisely, one is congruent to the result of a uniform scaling (enlarging or shrinking) of the other. **** Corresponding sides of similar polygons are in proportion, and corresponding angles of similar polygons have the same measure. One can be obtained from the other by uniformly "stretching" the same amount on all directions, possibly with additional rotation and reflection i.e., both have the same shape, or one has the same shape as the mirror image of the other. For example, all circles are similar to each other, all squares are similar to each other, all equilateral are similar to each other, and all parabolas are similar to each other. On the other hand, ellipses are //not// all similar to each other, //nor// are hyperbolas all similar to each other. If two angles of a triangle are equal to two angles of another triangle, then the triangles are similar.

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Now here are a few problems for you to try 1. Which one of these figures are similar figures?