1. GHSGT Practice Similar Figures & Transformations

2. Similar Figures Figures that have the same shape but not the same size Their corresponding sides can be written as a proportion: 7 14 6 12 10 20

3. Similar Figures Some questions will ask you to find the length of a missing side: Use a proportion and cross-multiply : 10 in. 5 in. x inches

4. Transformations Rotation – to move a figure around a fixed point (called the center of rotation) G ∙ Reflection – to flip a figure across a line; a mirror image G Translation – to move a figure as if you were sliding it in one directionG  G G

5. 1. Jamie has a picture that measures 12 inches in width and 24 inches in length. If Jamie enlarges the picture to make a poster 2 feet wide, how long is the poster? A. 2 ft B. 4 ft C. 6 ft D. 8 ft

6. 2. Find the missing length (x) for the pair of similar figures shown. A. 24 B. 28 C. 32 D. 36 18 14 12 16 28 24 32 x

7. 3. If the two triangles shown below are similar, find the measure of side x. A. 12 in. B. 24 in. C. 28 in. D. 48 in. 8 in. 24 in. x

8. 4. Study Figures I and II. Which transformation, if any, of Figure I, is shown in Figure II? A. no transformation B. reflection C. rotation D. translation Figure IFigure II

9. 5. Moving a geometric figure around a fixed point is transformation by A. inversion. B. reflection. C. rotation. D. translation.

10. 6. Study Figures I and II. Determine which transformation, if any, of Figure I is shown in Figure II. A. rotation B. reflection C. translation D. no transformation R  R Fig. IFig. II

11. Solutions 1. B – the ratio for the picture is 1:2. If the poster is 2 feet wide, then it is 4 feet long. 2. D – the corresponding side on the smaller figure is 18, and the ratio for the two figures is 1:2, so the correct length is 36. 3. C – the ratio for these triangles is 1:3, and the corresponding side of the smaller triangle is 8, so the correct length is 24 inches.

12. Solutions 4. B – the figure shows a reflection, or a mirror image. 5. C – The definition in this question is for a rotation. 6. C – the letter is slid from one place to another; this is a translation.