Answer:
Step-by-step explanation:
Let y represent the cost of buying the ticket.
Let x represent the number of days
in which the ticket was purchased before the departure day.
The relationship is inversely proportional because as x is reducing, y is increasing. The slope of the equation would be negative
Thus,
Slope = (239 - 189)/(0 - 20 = - 50/20 = - 2.5
If we apply the slope intercept form which is expressed as y = mx + c to model the equation, the y intercept, c would be 239 since it is the y value at which x = 0
The linear function used to model the situation becomes
y = - 2.5x + 239
The cost of the ticket when Marcus buys it for 3 days before his departure would be
y = - 2.5 × 3 + 239
y = - 7.5 + 239
y = $231.5
