Consider the three similar shapes below.

1. Find the lengths of the sides labeled with variables.

   Help (a):

   Find the scale factor between shapes A and B. To do so, compare two matching sides (one from each shape)
   and find the ratio of their lengths.

   More Help (a):

   Use this scale factor to divide or multiply the respective sides and solve for the unknown sides.

   Partial Answers (a):

   x = 3 ft
   z = 7 ft

2. What is the scale factor between shapes A and B?

   Help (b):

   What is the scale factor you found from part (a)?

3. What do you know about shapes A and C? Justify.

   Help (c):

   Shapes A and C are congruent, because they have a scale factor of $1$ (all side lengths and angles are the same).