5-2 Interpreting Graphs Warm Up Identify the quadrant that contains each point. 1. (6, –4) 2. (5, 3) 3. (–5, –2) lV l lll

5-2 Interpreting Graphs

Warm UpIdentify the quadrant that contains each point.

1. (6, –4)

2. (5, 3)

3. (–5, –2)

lV

l

lll


Learn to relate graphs to situations.


You can use a graph to show the relationship between speed and time, time and distance, or speed and distance.


Sp

eed

(m

i/h

r)

10

20

10 20 30 40 50

The graph at the right shows the varying speeds at which Emma exercises her horse. The horse walks at a constant speed for the first 10 minutes. Its speed increases over the next 7 minutes, and then it gallops at a constantrate for 20 minutes. Then it slows down over the next 3 minutes and then walks at a constant pace for 10 minutes.

Time (min)0


The height of a tree increases over time, but not at a constant rate. Which graph bests shows this?

Additional Example 1: Relating Graphs to Situations

As the tree grows, its height increases and then reaches its maximum height. Graph A shows the height of a tree not increasing but remaining constant. Graph C shows the height of a tree increasing at a constant rate without reaching a maximum height. The answer is graph B.

A. B. C.

5-2 Interpreting GraphsCheck It Out: Example 1

The dimensions of the basketball court have changed over the years. However, the height of the basket has not changed. Which graph bests shows this?

Graph A shows the height of the basket remaining constant. Graph C shows the height increasing without reaching a maximum height. Graph B shows the height increasing then remaining constant over time. The answer is graph A.

A. B. C.


Additional Example 2: Problem Solving Application

Jarod parked his car in the supermarket parking lot and walked 40 ft into the store and to the customer service counter, where he waited in line to pay his electric bill. Jarod then walked 60 ft to the back of the store to get 2 gallons of milk and walked 50 ft to the checkout near the front of the store to pay for them. After waiting his turn and paying for the milk, he walked back 50 ft to his car. Sketch a graph to show Jarod’s distance from his car over time. Use your graph to find the total distance traveled.


Additional Example 2 Continued

Sketch a graph that represents the situation. Then use the graph to find the total distance Jarod traveled.

22 Make a Plan

Time

Dis

tance

fro

m c

ar

(ft)

0

20

40

60

80

100

120



The distance increases from 0 to 40 feet when Jarod walks from the parking lot, where he parked his car, to the supermarket customer service counter. The distance does not change while he waits in line to pay his bill. The distance increases by 60 feet when he walks to the back of the store to get milk. The distance decreases as he walks back 50 feet to the checkout near the front of the supermarket. The distance does not change as he waits in line to pay for the milk. The distance decreases again as he walks another 50 feet back to his car in the supermarket parking lot.

Solve33

Jarod traveled a total of 200 feet.



Look Back44

Jarod walked from the supermarket parking lot to the back of the supermarket, approximately 100 feet. From the back of the supermarket he then returned to the parking lot, an additional 100 feet. The answer, 200 feet is reasonable since 100 plus 100 equals 200.


Lesson Quiz: Part I1. A ball is tossed into the air. Which graph best

shows this?

a. b.

b

Ele

vati

on

TimeEle

vati

on

Time


Lesson Quiz: Part II

2. Sam in-line skated 1,000 m from his home to the park, where he rested on a bench. He then returned home. Sketch a graph to show the distance he in-line skated compared to time. Use your graph to find the total distance traveled.

Dis

tan

ce (

m)

500

1,000

1,500

Time

2,000 m


1. Pressure decreases as altitude increases. Adams goes on a hiking trip to the top of a mountain and comes back. Which graph best shows this?

A. B.

Lesson Quiz for Student Response Systems

Time

Pre

ssu

re

Time

Pre

ssu

re


2. A wildlife photographer travels 4 miles from his camp to take pictures of lions, goes 8 miles farther to get pictures of deer, and then comes back to his camp. On his way back, he stops to take pictures of zebras that pass by.

Sketch a graph to show the photographer’s distance from his camp. Use the graph to find the total distance traveled by the photographer.

A. 24 mi B. 12 mi

Lesson Quiz for Student Response Systems

Time

Dis

tance

(m

i)

x

2

4

6

8

10

12

14y

Time

Dis

tance

(m

i)

x

2

4

6

8

10

12

14y

Documents

5-2 Interpreting Graphs Warm Up Identify the quadrant that contains each point. 1. (6, –4) 2. (5, 3) 3. (–5, –2) lV l lll