Function B: Function C: y=x+5

x y
0 3
4 -9
8 -21
(4 points)
Which function has a negative rate of change (slope)?

Which function has the smallest y-intercept?

Which function would you want to represent your money earned per hour?

Which function would give you the highest initial amount of money?

1 answer

To analyze the two functions, let’s first determine the equations represented by the points provided.

Function B: Points given are (0, 3), (4, -9), (8, -21). We can calculate the slope (rate of change) using the formula:

\[ \text{slope} = \frac{\text{change in } y}{\text{change in } x} = \frac{y_2 - y_1}{x_2 - x_1} \]

Let's use points (0, 3) and (4, -9):

\[ \text{slope} = \frac{-9 - 3}{4 - 0} = \frac{-12}{4} = -3 \]

Now let’s find the slope between (4, -9) and (8, -21):

\[ \text{slope} = \frac{-21 - (-9)}{8 - 4} = \frac{-21 + 9}{4} = \frac{-12}{4} = -3 \]

So, Function B has a negative slope (-3), indicating it has a negative rate of change.

Now let's look at Function C, which is given as \(y = x + 5\). The slope here is 1 (positive).

1. Which function has a negative rate of change (slope)?

  • Function B has a negative rate of change (slope of -3).

2. Which function has the smallest y-intercept?

  • The y-intercept of Function B (when \(x = 0\)) is \(y = 3\).
  • The y-intercept of Function C (when \(x = 0\)) is \(y = 5\).
  • Function B has the smallest y-intercept (3).

3. Which function would you want to represent your money earned per hour?

  • You would want a function with a positive slope to represent money earned per hour. Since Function C has a positive slope (1), it is more appropriate for this context.

4. Which function would give you the highest initial amount of money?

  • The initial amount of money corresponds to the y-intercept. As calculated, Function B has a y-intercept of 3, and Function C has a y-intercept of 5.
  • Therefore, Function C would give you the highest initial amount of money (5).

Summary:

  1. Function B has a negative rate of change.
  2. Function B has the smallest y-intercept.
  3. Function C is better for representing money earned per hour.
  4. Function C gives the highest initial amount of money.