To model the leak in a 15-gallon fish tank that loses 2 gallons of water each week, we can set up a function where \( y \) represents the amount of water in the tank after \( x \) weeks.
Initially, the tank has 15 gallons of water. Each week, it loses 2 gallons, so the amount of water in the tank decreases as time goes on.
The correct function can be expressed as:
\[ y = 15 - 2x \]
This indicates that at \( x = 0 \) (the start), \( y = 15 \), and for each week that passes (each increase in \( x \)), 2 gallons are subtracted from the initial 15 gallons.
Since none of the options you provided exactly match this function, the closest representation that models the situation is:
\[ y = -2x + 15 \]
So, the correct answer among the provided options is:
\[ y = -2x + 15 \]