1. Working with Ratio Segments (5.4.2)
April 6th, 2017

2. Triangle Proportionality Theorem
If a line parallel to one side of a triangle intersects the other two sides of the triangle, then the parallel line divides the two sides proportionally.
Why does this work?

3. Ex. 1: Solve for x, given that .

4. Converse of the Triangle Proportionality Theorem
Similarly, if the line divides the two sides of the triangle proportionally, then the line will be parallel to the third side of the triangle.

5. Ex. 2: Is ? Show your work to justify your answer.