Step 1: Write out the formula for a geometric sequence
[tex]\begin{gathered} T_n=ar^{n-1} \\ \text{Where} \\ T_n=\text{ the nth term} \\ a=\text{ the first term} \\ r=\text{ the common ratio} \end{gathered}[/tex]
Step 2: Write out the given values and find the formula
[tex]\begin{gathered} a=135, \\ r=-\frac{225}{135}=-\frac{5}{3} \end{gathered}[/tex]
Therefore the formula is given by
[tex]T_n=135(-\frac{5}{3})^{n-1}[/tex]
Hence, the correct choice is the first choice
