Activity Sheet on Using Proportionality Theorems

This activity sheet, containing twenty exercises, has students working with the proportionality theorem as they work with various diagrams containing parallel lines and triangles containing angle
bisectors.

Students will

• solve for X in four diagrams;

• solve for the lengths of various segments in two drawings; and

• complete a proof about angle bisectors in an isosceles triangle.

Answers for exercises are included.