Let \( t \) represent the total number of students in Ms. Garcia's class. According to the information, two-thirds of the class own a pet, and that number is equal to 8 students. We can express this relationship with the equation:
\[ \frac{2}{3} t = 8 \]
To complete the equation, you can rearrange it to express \( t \):
\[ t = \frac{8 \times 3}{2} \]
So the complete equation that models the total number of students \( t \) in Ms. Garcia’s class is:
\[ \frac{2}{3} t = 8 \]
Thus, the completed statement is:
\(\frac{2}{3} t = 8\).