Question

Beth borrows $100 from her grandmother and plans to pay her back $15 a month until the money is paid back. Which equation can be used to determine how much Beth will owe, y, after 5 months?

Answer 1

The equation to determine how much Beth will owe after 5 months is y = 100 - 15x. By substituting x with 5, we find out that Beth will owe $25 after 5 months.

Step-by-step explanation:

To determine how much Beth will owe, y, after 5 months of repaying a $100 loan to her grandmother at $15 a month without interest, we can use a simple linear equation. Initially, Beth owes $100. After each month, she pays back $15, so the amount she owes decreases by that amount each month. Therefore, after 5 months, the equation that determines the remaining balance would be:

y = 100 - 15x

Where x is the number of months that have passed. In this case, since we're interested in the amount owed after 5 months, we can substitute x with 5:

y = 100 - 15(5)

y = 100 - 75

y = 25

This shows that Beth will owe $25 after 5 months.