Two functions are represented in different ways.

Function 1:

Hours (x) Total cost (y)
0 $45
1 $75
2 $105
3 $135
Function 2: A contractor charges a flat rate of $50 and adds $40 for each hour worked.

Which statements are true?

Select each correct answer.

Responses

Function 2 has a greater y-intercept than function 1.
Function 2 has a greater y -intercept than function 1.

Function 1 has a greater rate of change than function 2.
Function 1 has a greater rate of change than function 2.

Function 2 has a greater rate of change than function 1.
Function 2 has a greater rate of change than function 1.

Function 1 has a greater y-intercept than function 2.

1 answer

To analyze the two functions and the statements, let's begin by determining the y-intercept and the rate of change for each function.

Function 1: The table provides the total cost (y) for given hours (x):

  • For 0 hours: $45
  • For 1 hour: $75
  • For 2 hours: $105
  • For 3 hours: $135

From this, we can calculate the y-intercept and rate of change:

  • The y-intercept (when x = 0): $45
  • Rate of change:
    • From the table, the total cost increases by $30 for each additional hour (for example, from 0 to 1 hour the cost increases from $45 to $75, which is an increase of $30).

Function 2: The function is described as charging a flat rate of $50 and adding $40 for each hour worked:

  • The cost function can be expressed as: \( y = 50 + 40x \)

From this function:

  • The y-intercept (when x = 0): $50
  • Rate of change: The rate of change is the coefficient of x which is $40 (the cost increases by $40 for each additional hour).

Now we can evaluate the statements:

  1. Function 2 has a greater y-intercept than function 1.

    • True. (Function 2's y-intercept is $50, which is greater than Function 1's $45.)
  2. Function 1 has a greater rate of change than function 2.

    • False. (Function 1's rate of change is $30; Function 2's is $40.)
  3. Function 2 has a greater rate of change than function 1.

    • True. (Function 2's rate of change is $40, which is greater than Function 1's $30.)
  4. Function 1 has a greater y-intercept than function 2.

    • False. (Function 1's y-intercept is $45, which is less than Function 2's $50.)

Summary of True Statements:

  • Function 2 has a greater y-intercept than function 1.
  • Function 2 has a greater rate of change than function 1.