To represent the cost of a drink with the variable \( x \), we can set up the equation based on the information provided:
\[ 3.19 + x = 5.61 \]
Now, we will solve for \( x \):
- Subtract \( 3.19 \) from both sides of the equation:
\[ x = 5.61 - 3.19 \]
- Perform the subtraction:
\[ x = 2.42 \]
Therefore, the cost of the drink is \( \boxed{2.42} \).