toLet the number of trout = x
And the number of bass = y
gaming laws allow you to catch no more than 15 trout per day, no more than 10 basses per day.
So,

And no more than 20 total fish per day
So,

We will check if you can catch 11 trout and 9 bass
So, x = 11 and y = 9
So, 11 < 15
and 9 < 10
And (11+9) = 20
so, the answer of the question will be Yes
Because 11 trout and 9 basses are achieving the previous inequalitues.