Page 699 - Basic College Mathematics with Early Integers

676 C HAPTE R 9 I GEOMETRY

27. 28.
15 100
n 100 7 10q 20
8
82
82
n

37.5

Solve. For Exercises 29 and 30, the solutions have been started for you. See Example 4.

29. Given the following diagram, approximate the 30. Fountain Hills,Arizona, boasts the tallest fountain in
height of the observation deck in the Seattle Space the world.The fountain sits in a 28-acre lake and
Needle in Seattle,Washington. (Source: Seattle shoots up a column of water every hour. Based on the
Space Needle) diagram below, what is the height of the fountain?

n

13 ft

80 ft 2 ft

Start the solution: Start the solution:
1. UNDERSTAND the problem. Reread it as many 1. UNDERSTAND the problem. Reread it as many
times as needed. times as needed.
2. TRANSLATE into a proportion using the similar 2. TRANSLATE into a proportion using the similar
triangles formed. (Fill in the blanks.) triangles formed. (Fill in the blanks.)

height of length of Space height of tree : 28 ; length of tree

observation deck : n = ; Needle shadow = shadow
height of pole : 13 ; length of pole height of fountain : n ; length of fountain
shadow shadow
3. SOLVE by setting cross products equal.
3. SOLVE by setting cross products equal.
4. INTERPRET.
4. INTERPRET.
31. Given the following diagram, approximate the 32. The tallest tree standing today is a redwood located in
height of the Bank One Tower in Oklahoma City, the Humboldt Redwoods State Park near Ukiah,
Oklahoma. Here, we use x to represent the unknown California. Given the following diagram, approximate
number. (Source:The World Almanac) its height. Here, we use x to represent the unknown
number. (Source: Guinness World Records)
Copyright 2012 Pearson Education, Inc.

x
x

10 feet
25 feet
73 feet 2 feet
40 feet 2 feet