Comparing Rate of Change and Y-Intercept

Aunt Maggie’s car broke down on Interstate10. Sam’s Towing charges a $57 hook up fee and $2 per mile towed. Regina’s Towing charges a $45 hook up fee and $2.50 per mile towed. Which of the following is NOT true?

• Both situations can be modeled using linear functions.

• The rate of change of the function that models Regina’s towing charge is 2.5

• The intercept of the functions that model both situations represents the hook up fee.

• The rate of change of the functions that model both situations represent the miles traveled per hour.

Which of the following is the graph of Maggie and Regina's towing situation.

y = 2x + 57

y = 2.5x + 45

• 
• 

What is the formula for slope-intercept form?

• ax + by = c

• y=mx+b

• y=b+mx

• by+ax=c

1. Consider the following equations.

Equation A: 4x - 2y = -6

Equation B: 3x + y = 3

Which of the following statements is true?

• The slopes of both lines are the same and the y-intercepts are different.

• The slopes of both lines are different and the y-intercepts are the same.

• The slopes and the y-intercepts of both lines are the same.

• The slopes and the y-intercepts of both lines are different.

Appleseed, a tech company, spends a fixed cost of $1500 to manufacture the wristbands for their new Appleseed Watch, plus $100 per unit manufactured.

What is the slope of the line?

• 1500

• 100

• 1500x

• 100x

Appleseed, a tech company, spends a fixed cost of $1500 to manufacture the wristbands for their new Appleseed Watch, plus $100 per unit manufactured.

What is the y-intercept?

• 1500

• 100

• 1500x

• 100x

1. You saved $300 to spend over the summer. You decide to budget $50 to spend each week.

Write an equation (in slope-intercept form) that represents this situation.

• y = 300x + 50

• y = 300 + 50x

• y = 50x + 300

• y = 50 + 300x

You saved $300 to spend over the summer. You decide to budget $50 to spend each week.

What is the slope of the line?

• 300

• 50

• 300x

• 50x

You saved $300 to spend over the summer. You decide to budget $50 to spend each week.

What is the y-intercept of the line?

• 300

• 50

• 300x

• 50x

y = -2x - 4

Identify the slope and y-intercept.

• slope = 2

  y - intercept = 4

• slope = -2

  y-intercept = 4

• slope = 2

  y-intercept= -4

• slope = -2

  y-intercept = -4