Answer:
(10,1)
Explanation:
Let No. of iced tea be x
Let no. of lemonades be y
We are given that You need to purchase at least 9 gallons of drinks
So, equation becomes:
--1
Cost of 1 gallon of ice tea = $4
Cost of x gallons of ice tea = $4x
Cost of 1 gallon of lemonade = $6
Cost of y gallons of lemonade = $6y
We are also given that you have at most $55 to spend.
So, equation becomes:
---2
Now Check the given points which satisfies the inequalities
and

At (10,10)
and

and
(10,10) is not satisfying the both equations
At (10,-5)
and

and
(10,-5) is not satisfying the both equations
At (2,10)
and

and
(2,10) is not satisfying the both equations.
At (10,1)
and

and
(10,1) is satisfying the both equations.
Thus (10,1) is a possible solution to the system of inequalities