Download Module 2 Lesson 25 with Notes

GEOMETRY
MODULE 2 LESSON 25
INCREDIBLY USEFUL RATIOS
OPENING EXERCISE
Use your notes from Lesson 24 to label each side of the triangles below.
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WORKBOOK
Complete Exercise 1 thru 3.
DISCUSSION
Another common way of labeling the sides of triangles is to make
use of the relationship between a vertex and the side opposite the
vertex and the lowercase letter of each vertex angle.
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Another set of labels is specific to right triangles.

Label ∠𝐵 as the right angle.

Of the two acute angles, we will focus our attention on labeling ∠𝐴.
Mark ∠𝐴 with a single arc.

̅̅̅̅ is the opposite side, label as opp.
With respect to ∠𝐴, side 𝐵𝐶

̅̅̅̅ is the adjacent side, label as adj.
With respect to ∠𝐴, side 𝐴𝐵

The hypotenuse is always opposite the 90° angle. Label as hyp.
WORKBOOK
Complete Exercise 4 thru 6.
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GROUP ACTIVITY
Group 1: Left side of room complete the chart for Group 1. Use triangles on page 193
Group 2: Right side of room complete the chart for Group 2. Use triangles on page 195
𝑜𝑝𝑝
𝑎𝑑𝑗
NOTE: Regardless of the side measures, the ratios for ℎ𝑦𝑝 and ℎ𝑦𝑝 always results in the same value for
corresponding congruent angles. Compare the rows between the two charts.
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WORKBOOK
10. From a point 120 m away from a building, Serena measures the angle between the ground and the
top of a building and finds it measures 41°. What is the height of the building? Round to the nearest
meter.
SUMMARY
HOMEWORK

Problem Set Module 2 Lesson 25 page 189: #1-7

Due: Wednesday, Dec 14 (Corrections)
No late work will be accepted after this date.
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