Given an exponential function for compounding interest, A(x) = P(0.77)^x , what is the rate of change as a percentage?

Solution:
An exponential function is expressed as
[tex]\begin{gathered} y=a(1+r)^x--\text{ equation 1} \\ where \\ r\Rightarrow rate\text{ of change} \end{gathered}[/tex]Given the exponential function:
[tex]A(x)=P(0.77)^x---\text{ equation 2}[/tex]By comparison, we have
[tex]\begin{gathered} 0.77=1+r \\ add\text{ -1 to both sides,} \\ 0.77-1=-1+1+r \\ \Rightarrow r=-0.23 \\ In\text{ percentage, we have} \\ r=-23\% \end{gathered}[/tex]Hence, the correct option is