To model Giselle's situation with a linear function, we need to define the variables involved.
Let:
- \( b \) be the balance in her account after using the club,
- \( x \) be the number of times she uses the club.
Initially, Giselle pays $210 in advance. Each time she uses the club, $15 is deducted from her account. Therefore, we can express her account balance as follows:
- Start with an initial balance of $210.
- Each time she uses the club (represented by \( x \)), $15 is deducted, so we subtract \( 15x \) from the initial balance.
This leads us to the equation:
\[ b = 210 - 15x \]
So the correct function that models the situation is:
\[ b = 210 - 15x \]
Therefore, the answer is:
b = 210 – 15x