Proportions and Similarity Proportional Parts and Parallel Lines

Proportional Parts and Parallel Lines You will learn to identify and use the relationships between parallel lines and proportional parts.

Proportional Parts and Parallel Lines On your given paper, draw two (transversals) lines intersecting the parallel lines. Label the intersections of the transversals and the parallel lines, as shown here. Do the parallel lines divide the transversals proportionally? Yes

Proportional Parts and Parallel Lines If l || m || n

Proportional Parts and Parallel Lines Find the value of x. HJ GH VW UV 18 12 x 15 12x = 18(15) 12x = 270

Proportional Parts and Parallel Lines If l || m || n and Then

Proportional Parts and Parallel Lines (x +3) 10 (2x – 2) 10 Find the value of x. F (x + 3) = (2x – 2) x + 3 = 2x – 2 Theorem 9 - 9 8 8 E D C B A

Proportional Parts and Parallel Lines