Question

Complete the following problems.
Amy has $50 in her lunch account. Amy spends $3 a day for lunch. Amy's mother receives a notification when Amy's
account balance reaches $5 or lower. How many lunches can Amy purchase until her mother receives a notification? And what is the equation in slope intercept form

Answer 1

Answer:

Amy can purchase up to 14 lunches until her mother receives the notification. When she has the 15th lunch, the notification will be sent.

Step-by-step explanation:

The balance Amy has in her lunch account is a function of the number of lunches she has consumed.

The initial balance is $50 and it decreases by $3 for every lunch Amy has. Thus, the function that models the balance in her lunch account is:

$B(x)=50-3x$

Where x is the number of lunches.

Her mother receives a notification when the balance goes at $5 or lower, thus the condition that triggers the notification is:

$B(x) \le 5$

Or, equivalently:

$50-3x\le 5$

Subtracting 50:

$-3x\le 5-50$

$-3x\le -45$

Multiplying by -1 (and flipping the sign):

$3x\ge 45$

Solving:

$x\ge45/3$

$x\ge 15$

Amy can purchase up to 14 lunches until her mother receives the notification. When she has the 15th lunch, the notification will be sent.