In this lesson, you learned how to:

• Explain when a relationship between two quantities is a function.
• Identify independent and dependent variables in a function, and use words and graphs to represent the function.
• Explain what descriptions and graphs of functions tell us about situations.

Here are the activities that helped you reach those goals:

• 4.1.1: Contrasting Two Relationships by Reasoning
  • In this activity, you looked at which relationships represent a function and learned which quantities are functions of the other.
• 4.1.2: Reasoning Graphically About the Relationship between the Two Quantities
  • In this activity, you sketched graphs about a dog’s movement as distance was a function of time.
  • 4.1.2: Self Check
  • 4.1.2: Additional Resources
• 4.1.3: Examining Relations and Functions
  • In this activity, you determined if relations are functions by looking at the given inputs and outputs.
  • 4.1.3: Self Check
  • 4.1.3: Additional Resources
• 4.1.4: Describing Functional Relationships
  • In this activity, you identified the independent and dependent variables in functional relationships. You also determined which variable was a function of the other to make statements about the relationship.
  • 4.1.4: Self Check
  • 4.1.4: Additional Resources
• 4.1.5: Modeling Relationships between Two Variables
  • In this activity, you summarized everything you have learned in this lesson by identifying independent and dependent variables of a situation, determining which variable is a function of the other, and sketching a graph of the situation.

After these activities, you completed the following practice:

• 4.1.6: Practice