Question

nevaeh uses a gift card to buy a cup of coffee every morning. the table shows the amount of money left on the card, y, as a function of the number of cups of coffee she buys, x. find and describe the rate of change of the function. the rate of change is. it represents in the amount on the gift card for every cup nevaeh purchases. number of cups of coffee, x: 2, 5, 7; amount of money left on card ($), y: 19, 10, 4

Explanation:

Step1: Recall rate - of - change formula

The rate of change formula for a function $y = f(x)$ between two points $(x_1,y_1)$ and $(x_2,y_2)$ is $m=\frac{y_2 - y_1}{x_2 - x_1}$.

Step2: Select two points from the table

Let $(x_1,y_1)=(2,19)$ and $(x_2,y_2)=(5,10)$.

Step3: Calculate the rate of change

$m=\frac{10 - 19}{5 - 2}=\frac{-9}{3}=- 3$.

Answer:

-3; a decrease