1. Writing and Graphing Equations in the Form y = mx + b
7.2
Writing and Graphing Equations in the Form y = mx + b
How do you write and graph a linear relationship?

2. ADDITIONAL EXAMPLE 1
Fiona manages an edible arrangements business that charges $15 per container plus $2.50 for each ounce of fruit in the arrangement. Write an equation to describe the linear relationship.
y = 2.5x + 15

3. ADDITIONAL EXAMPLE 2
Kyle has signed up for a cell phone plan that costs $60 per month plus a one-time activation fee of $40. Represent the relationship using a table, an equation, and a graph.
y = 60x + 40

4. 7.2 LESSON QUIZ
7.7 1.
A summer movie club charges a $30 membership fee and then $5 per movie. Write an equation to describe the linear relationship.
y = 5x + 30

5. 2.
A puzzle company charges $10 per puzzle plus $5 to deliver each order by mail. Graph the linear relationship.

6. 3.
Peter currently owns $450 worth of movie DVDs. He spends $15 each week on a new movie. Represent the relationship between the value of his movie collection and the number of weeks using a table and an equation. Let last week be Week 0.
y = 15x + 450

7. 4.
Suppose you have a dog-walking business after school for which you charge each customer $3 per hour plus an additional $10. a.
Write an equation to describe the linear relationship.
y = 3x + 10 b.
State the meaning of the ordered pair (8, 34).
If you walk a dog for 8 hours in one week, you will earn $34.

8. How do you write and graph a linear relationship?
Sample answer:
Make a table and record different values for the linear relationship. Use the table to create ordered pairs, and then graph the ordered pairs on a coordinate grid.