1. Chapter 7

2. A B C A' B' C' We write ΔABC = Δ A'B'C' ~

3. A B C A' B' C' We write ΔABC ~ ΔA'B'C'

4. Transforms a figure into an isometric figure  Translation (t)  Rotation (r)  Reflection (s)  Glide reflection (gr) Transforms a figure into a similar figure  Dilation: Enlarge or reduce from the initial (1 st ) to the image (2 nd ) *think of a photo copy machine *** dilation + any isometry = composition (which is a similitude)

6. Ratio: measure of image measure of initial Ratio: 1 or 2 or 3 5 10 15 Ratio is k=0.2 Initial Image 5 10 15 1 2 3

8. Initial Image 4cm 6cm 8cm 12cm Ratio of sides: k = 12 6 k = 2 Ratio of perimeters: k = 40 20 k = 2 Perimeter: 20cm Perimeter: 40cm

9. Scale factor: k perimeter of initial X k = perimeter of the image

10. Initial Image 6 cm 10 cm 24 cm Step 1 - Find the missing side of initial triangle (use Pythagoras) missing side: 8cm Step 2 – Calculate perimeter of the initial p = 8+6+10 p=24 Step 3 – Find k k = 24 = 3 8 Step 4 – Calculate the perimeter of the image P=24 x 3 = 72cm Find the perimeter of the image

11. Workbook p. 216 (all) p. 217 Activity 3 p.221 #1,2,3