Page 132 - Algebra 1

INVES2TIGATION
Graphing a Relationship
A graph is a visual representation of how data change and relate to each other. A graph can convey the numeric relationship between data like time and distance.
BeachTrip Mariatakesatriptothebeach. She stays at the beach all day before driving back home. As Maria drives to the beach, her distance from home increases. While she is at the beach, there is no change in her distance from home. As she returns home, her distance from home decreases.
Trip to the Beach
Time
Horse’sSpeed Thegraphshowsthevariousspeedsatwhichahorsetravels. Horse’s Practice Run
30 20 10
Online Connection www.SaxonMathResources.com
0
10 20 30 40 50
Time (min)
1. Analyze Use the graph to complete the table. Describe the horse’s speed in each of the time intervals as increasing, no change, or decreasing.
Interval
Description
0 to 10 minutes
10 to 18 minutes
18 to 38 minutes
38 to 40 minutes
40 to 50 minutes
Math Reasoning
Analyze How does the increase in the horse’s speed compare to the decrease in its speed? Explain.
You can use a graph to show how data change. When drawing a graph to represent a real-world situation,
• choose appropriate intervals for the units on the axes;
• be sure to space the intervals equally;
• only use values that make sense, such as positive numbers of books
or whole numbers of people.
Investigation 2 117
Speed (mph)
Distance from Home