1. Similar Figures
To find an unknown side length in similar figures:
Given , find DF Given , find WX
3. Given The length AB is 10. The length BC is 7.
Find the length XY if the length YZ is 14.
Use the ratios of the lengths of corresponding sides to write a proportion involving the unknown length.

2. INDIRECT MEASUREMENT!
You can use proportions (similar triangles) to find the height of things you may not otherwise be able to determine.
4. What is the height of the tree? What is the height of the building?
6. Steven is using similar triangles to find the height of a tree. Steve is 6ft tall and casts a shadow
that is 4ft long. The tree casts a shadow that is 32 feet long. How tall is the tree?