Graphs

Recording scientific findings

The Importance of

Graphs

Line Graphs

O Graphs are a “picture” of your data.

O They can reveal patterns or trends

O Used to show how one variable changes in response to another variable. (independent & dependent variables)

Parts of a Line Graph

OHorizontal Axis (x-axis) runs left to right.

OVertical Axis (y-axis) runs up and down

OOrigin – is the point where they cross

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Parts of a Line Graph

Labeling a Line Graph

O Data Points: shows the location of a piece of data.O Coordinate: a pair of

numbers used to determine the position of a point on a graph

O X-axis is used for independent variable (what you manipulated)

O Y-axis is used for Dependent Variable (Measureable outcome)

Labeling a Line Graph

(cont.)

Two Types of Line Graphs:

O A line: shows the trend of the data

O A title: Explains what the graph shows

O Linear: data points yield a straight line

O Non-linear: data points do not yield a straight line.

Using Graphs to Identify Trends:

O Types of Trends:

O Linear: straight line

O Nonlinear: may be a curve or level off

O No trend: data points are scattered no pattern

Interpreting Data Summary:

OAnswer the following question as your summary:

OCould you use a line graph to show data about how the height of a plant changes with the number of hours of light? Explain.

Answer to questionsO A line graph could show the data by

labeling the x-axis (horizontal) with the independent variable (manipulated- the number of hours of light) and the y-axis (Vertical) with the dependent variable (measurable/responding data – height of the plant).

Left hand Activity: Explain and show different graph trends :

ODraw a picture of each graph example:OLinearONon-LinearONo Trend