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Explore the concept of geometric mean between two numbers and its relevance in geometry. Discover how altitude drawn in a right triangle relates to geometric means. Practice finding geometric means with provided examples. Learn how to identify the "W" pattern and apply proportions to solve for geometric means. Dive into Theorem 7.1 and Theorem 7.2 to deepen your understanding.
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Lesson 7-1 Geometric Mean Lesson 7-1: Geometric Mean
The geometric mean between two numbers a and b is the positive number x where . Therefore x = . Try It: Find the geometric mean of . . . Answer = 20 1. 10 and 40 2. 1 and 36 Answer = 6 3. 10 and 20 Answer = 14.14 4. 5 and 6 Answer = 5.48 Answer = 9.94 5. 8.1 and 12.2 Lesson 7-1: Geometric Mean
A B C How does this relate to geometry? Lesson 7-1: Geometric Mean
If the altitude is drawn from the vertex of the 90° angle of a Right ▲ to its hypotenuse, then the two new ▲s formed are similar to the original ▲ andto each other.Example: ▲ABC ~ ▲DBA ~ ▲DAC Theorem 7.1 Lesson 7-1: Geometric Mean
The " W " Pattern Lesson 7-1: Geometric Mean
The Geometric Means Recall the three geometric means that you discovered from your Sketchpad activity. BUT FIRST . . . Lesson 7-1: Geometric Mean
Re-label the Sides (as lengths) Lesson 7-1: Geometric Mean
Geometric Mean #1 What is the proportion that uses f? f is the geometric mean of d and e. Lesson 7-1: Geometric Mean
Geometric Mean #2 What is the proportion that uses b? b is the geometric mean of e and c. Lesson 7-1: Geometric Mean
Geometric Mean #3 What is the proportion that uses a? a is the geometric mean of d and c. Lesson 7-1: Geometric Mean
Put them all together Lesson 7-1: Geometric Mean
The “W” Pattern W Lesson 7-1: Geometric Mean
The measure of an altitude drawn from the vertex of the 90° angle of a Right ▲ to its hypotenuse is the geometric mean between the measures (lengths) of the two segments of the hypotenuse.Example: AD is the geometric mean of BD and DC. Theorem 7.2 Lesson 7-1: Geometric Mean
Try it ! Given: d = 4 and e = 10 Find: a = ___ b = ___ c = ___ f = ___ Lesson 7-1: Geometric Mean
Solution: Proportions Answers Lesson 7-1: Geometric Mean