Ratios:  http://goo.gl/03SiO4

Unit Rates:  http://goo.gl/OIC2X

Proportions:  http://goo.gl/oFmGUB

Unit Scale:  http://goo.gl/n7pGrK

Scale Factor:  http://goo.gl/cNJ2a7

Similar Triangles, AA: http://goo.gl/muZ2eG

Similar Triangles, SSS: http://goo.gl/HMRknZ

Problem Solve With Sim Tri: http://goo.gl/vVbxfx

Similar Tri. for Missing parts:   http://goo.gl/dhig9t

Tri. Prop. Theorem: http://goo.gl/d4NPmq

Use Tri. Prop. Theorem:  http://goo.gl/d4NPmq

Find the Missing Length on Similar Triangles When They Are Separate:  http://goo.gl/tgKxiI

Find the Missing Length on Similar Triangles When They Overlap:  http://goo.gl/9SnOCk

The Triangle Angle Bisector Theorem:  http://goo.gl/nQL9HG

Use the Tri. Ang. Bisect. Theorem  to Find Missing Lengths:  http://goo.gl/2flSq6