Lesson 8.7: Help for Exercises 22 and 23 on page 511
Carefully read the directions for these exercises and notice that there are four parts to each answer: a sketch, reduction or enlargement, scale factor, and missing lengths. As you sketch the dilation, you do not need to include a center of dilation because you are given no information about it. Using the given lengths, draw two similar triangles, ABC and A'B'C' and label the side lengths Try to draw roughly to scale. You will be able to see whether A'B'C' is smaller or larger than ABC, indicating reduction or enlargement. The scale factor of the dilation is the same as the ratio of the lengths of corresponding sides. Make sure the scale factor is less than 1 for a reduction and greater than 1 for an enlargement. Write and solve proportions to find the missing lengths.