Interpreting Graphs and Tables

1
Interpreting Graphs and Tables

• Investigation 2-2

2
Todays Learning Goal

• We will continue to develop our understanding
  that the rate of change between two variables is
  associated with its equation, table of values,
  and graph.
• We will continue to develop our understanding
  that for linear relationships, for every 1
  increase in one variable, there is a constant
  rate of change in the other variable.
• We will begin to understand how a starting value
  affects the table, graph, and equation.

3
Walking for Charity

• Ms. Changs class decided to participate in a
  walkathon to raise money for a local hospital.
  The class wants to agree on how much money they
  will ask each sponsor to pledge.
• Leanne says that 1 per mile would be
  appropriate.
• Gilberto says that 2 per mile would be better
  because it would bring in more money.
• Alana points out that if they ask for too much
  money, not as many people will want to be
  sponsors. She suggests that they ask each
  sponsor for a 5 donation plus 50 per mile.

4
Partner Work

• You have 30 minutes to work on the following
  questions with your partner.

5
For those that finish early

• 1. a) On the graph of a pledge plan, the point
  (2, 6) means that a student who walks 2 miles
  earns 6 from each sponsor. On which of the
  graphs is the point (2,6)?
• b) Find a point on each graph, and describe
  what the coordinates of the point mean in the
  context of the walkathon.
• 2. a) Write an equation for a pledge plan whose
  graph is a steeper line than any of the lines you
  graphed in the problem.
• b) Write an equation for a pledge plan whose
  graph is less steep than any of the lines you
  graphed in the problem.

6
Big Ideas from Todays Lesson

• A starting value like the 5 donation in this
  problem shows up in the table when the
  independent variable is 0, it shows up in the
  graph on the vertical axis, and it shows up in
  the equation by being added on.
• A difference in rate changes the steepness of a
  graph the higher the rate, the steeper the
  graph.

7
Homework

• Complete the homework worksheet.
• A grid paper is given to you so that you can do
  your graph on it.