1 ANALYTIC GEOMETRY TOPIC 2 | LESSON 1 MR. LOHUIS TRIANGLE PROPORTIONALITY THEOREM

KEY CONCEPTS A transversal is a line that cuts through two parallel lines. When a triangle contains a line that is parallel to one of its sides, the two triangles formed can be proved similar using the AA Similarity Postulate. Since triangles are similar, their sides are proportional. The three midsegments of a triangle form the Midsegment Triangle. 2

TRIANGLE PROPORTIONALITY THEOREM 3

CONVERSE OF TRIANGLE PROPORTIONALITY THEOREM 4

TRIANGLE MIDSEGMENT THEOREM 5

KEY CONCEPTS A transversal is a line that cuts through two parallel lines. When a triangle contains a line that is parallel to one of its sides, the two triangles formed can be proved similar using the AA Similarity Postulate. Since triangles are similar, their sides are proportional. The three midsegments of a triangle form the Midsegment Triangle. 6