The form of the linear function is
[tex]y=mx+b[/tex]
m is the rate of change
b is the initial amount
Since the given equation is
[tex]C(q)=27500-2500q[/tex]
Where C(q) represents the balance in the account after q quarters
Compare the equation by the form of the function above, then
[tex]\begin{gathered} m=-2500 \\ b=27500 \end{gathered}[/tex]
Since m is a negative number, then the rate is decreasing
The balance in this account is decreasing at the rate of 2500 dollars per quarter
Since the value of b is 27500, then
After 0 quarters, the balance in this account is $27500
We need to find the value of q when C(q) = 0
Substitute C by 0 in the equation and solve to find q
[tex]0=27500-2500q[/tex]
Add 2500q to both sides
[tex]\begin{gathered} 2500q=27500-2500q+2500q \\ 2500q=27500 \end{gathered}[/tex]
Divide both sides by 2500
[tex]\begin{gathered} \frac{2500q}{2500}=\frac{27500}{2500} \\ q=11 \end{gathered}[/tex]
You can pay for 11 quarters before the money in this account is gone