Step 1 Determine the x-axis and y-axis variables. Time varies independently of distance and is plotted on the x-axis. Distance is dependent on time and is plotted on the y-axis.

Step 2 Determine the scale of each axis.The x-axis data ranges from 0 to 5.The y-axis data ranges from 0 to 40.

Step 3 Using graph paper, draw and label the axes. Include units in the labels.

Step 4 Draw a point at the intersection of the time value on the x-axis and corresponding distance value on the y-axis.Connect the points and label the graph with a title, as shown in Figure 20.

Distance v. Time

Figure 20 This line graph shows the relationship between distance and time during a bicycle ride.

Figure 20 This line graph shows the relationship between distance and time during a bicycle ride.

Practice Problem A puppy's shoulder height is measured during the first year of her life.The following measurements were collected: (3 mo, 52 cm), (6 mo,72 cm), (9 mo,83 cm),(12 mo,86 cm).Graph this data.

Find a Slope The slope of a straight line is the ratio of the vertical change, rise, to the horizontal change, run.

g _ verticalchange (rise) _ change in y p horizontal change (run) change in x

Example Find the slope of the graph in Figure 20.

Step 1 You know that the slope is the change in y divided by the change in x.

Slope _ changein y change in x

Step 2 Determine the data points you will be using. For a straight line, choose the two sets of points that are the farthest apart. (40-0) km

Slope _

Step 3 Find the change in y and x. 40km

Slope _ "5iT

Step 4 Divide the change in y by the change in x. 8 km

Slope _

The slope of the graph is 8 km/h.

Bar Graph To compare data that does not change continuously you might choose a bar graph. A bar graph uses bars to show the relationships between variables. The x-axis variable is divided into parts. The parts can be numbers such as years, or a category such as a type of animal. The y-axis is a number and increases continuously along the axis.

Example A recycling center collects 4.0 kg of aluminum on Monday, 1.0 kg on Wednesday,and 2.0 kg on Friday.Create a bar graph of this data.

Step 1 Select the x-axis and y-axis variables.The measured numbers (the masses of aluminum) should be placed on the y-axis.The variable divided into parts (collection days) is placed on the x-axis.

Step 2 Create a graph grid like you would for a line graph. Include labels and units.

Step 3 For each measured number,draw a vertical bar above the x-axis value up to the y-axis value. For the first data point, draw a vertical bar above Monday up to 4.0 kg.

Aluminum Collected During Week

Practice Problem Draw a bar graph of the gases in air: 78% nitrogen, 21% oxygen, 1% other gases.

Circle Graph To display data as parts of a whole, you might use a circle graph. A circle graph is a circle divided into sections that represent the relative size of each piece of data. The entire circle represents 100%, half represents 50%, and so on.

Example Air is made up of 78% nitrogen, 21% oxygen, and 1% other gases. Display the composition of air in a circle graph.

Step 1

Multiply each percent by 360° and divide by 100 to find the angle of each section in the circle.

Step 2 Use a compass to draw a circle and to mark the center of the circle. Draw a straight line from the center to the edge of the circle.

Use a protractor and the angles you calculated to divide the circle into parts. Place the center of the protractor over the center of the circle and line the base of the protractor over the straight line.

Other

Nitrogen 78%

Practice Problem Draw a circle graph to represent the amount of aluminum collected during the week shown in the bar graph to the left.

Was this article helpful?

Get All The Support And Guidance You Need To Be A Success At Helping Save The Earth. This Book Is One Of The Most Valuable Resources In The World When It Comes To How To Recycle to Create a Better Future for Our Children.

## Post a comment