write a linear equation that models

you borrow $120 from your brother. You plan to pay him $15 per week towards the loan.

120=15x

or
y=15x-120

This is right.

120=15x

To model the situation as a linear equation, we need to consider the variables and their relationship. In this case, we have the amount borrowed ($120) and the weekly payments ($15).

Let's define our variables:
- The amount borrowed: Let's call it A.
- The number of weeks passed: Let's call it x.
- The amount paid back: Let's call it P.

Now, we know that the total amount borrowed is $120. So we can write a simple equation:

A = $120

We also know that each week you plan to repay $15. So after x weeks, you would have paid back a total of 15x dollars.

P = $15x

Now, the amount paid back is subtracted from the original amount borrowed:

A - P = 0
$120 - ($15x) = 0

Simplifying the equation gives us:

$120 - $15x = 0

This equation models the relationship between the amount borrowed, the number of weeks passed, and the amount paid back.