Present how to use the triangle proportionality theorem (if a line parallel to one side of a triangle intersects the other two sides, then it divides the two sides proportionally) to solve for unknown variables and unknown side lengths.
Present the converse of the triangle proportionality theorem (if a line divides two sides of a triangle proportionally, then it is parallel to the third side).
Define the midsegment of a triangle, and how it is parallel to the third side and is half as long.
Provide examples that demonstrate how to solve for unknown variables and side lengths using the midsegment theorem.
This packet should help a learner seeking to understand the triangle proportionality theorem and its converse.
This video presents how to use the triangle proportionality theorem to solve for unknown variables and unknown side lengths.
This video introduces the converse of the triangle proportionality theorem (if a line divides two sides of a triangle proportionally, then it is parallel to the third side).
This video defines the midsegment of a triangle, and explains how it is parallel to the third side and is half as long.