To find the total amount Samuel spent at the farmers market on both days, we can calculate the expenses for each day and then combine them.
On the first day:
- He bought 3 pounds of apples at \( x \) dollars per pound: \[ 3x \]
- He bought 2 bags of spinach at \( y \) dollars each: \[ 2y \]
- Therefore, the total amount spent on the first day is: \[ 3x + 2y \]
On the second day:
- He bought 5 pounds of apples at \( x \) dollars per pound: \[ 5x \]
- He bought 3 bags of spinach at \( y \) dollars each: \[ 3y \]
- Therefore, the total amount spent on the second day is: \[ 5x + 3y \]
Now, we add the total amounts spent on both days: \[ (3x + 2y) + (5x + 3y) = 3x + 5x + 2y + 3y = 8x + 5y \]
Thus, the total amount spent at the market on both days is represented by the expression: \[ \boxed{8x + 5y} \]