Geometry – 7.4 Parallel Lines and Proportional Parts NOTES

x Mid-segment of a triangle: a segment with endpoints that are on midpoints of two sides of the triangle

Example 1: Find the Length of a Side

Refer to the figure to the right to answer the following questions.

1)

2)

Geometry – 7.4 Parallel Lines and Proportional Parts NOTES

Example 2: Determine if Lines are Parallel

Refer to the figure to the right to answer the following questions.

3)

4)

Geometry – 7.4 Parallel Lines and Proportional Parts NOTES

Example 3: Use the Triangle Midsegment Theorem

5) XZ 6) ST

7) 𝑚∠𝑅𝑌𝑋

Use the figure to the left to find each

measure.

8) DE 9) DB

10) m∠FED

Geometry – 7.4 Parallel Lines and Proportional Parts NOTES

Example 4: Use Proportional Segments of Transversals

11) Megan is drawing a hallway in one-point perspective. She uses the guidelines shown to draw two windows on the left wall. If segments 𝐴𝐷, 𝐵𝐶, 𝑊𝑍, 𝑋𝑌 are all parallel, AB = 8 centimeters, DC = 9 centimeters, and ZY = 5 centimeters, find WX.

Example 5: Use Congruent Segments of Transversals

12) Find x and y.

13) Find x.