Answer:
The possible solution to the system of inequalities is:
 Option: D
 D. (10,1)
Explanation:
Iced tea, x, costs $4 per gallon and lemonade, y, costs $6 per gallon. 
 You need to purchase at least 9 gallons of drinks for a neighborhood picnic, but have at most $55 to spend. 
This means that the inequalities that will be formed using the above information is:
 

and 

Now, we will put the point in the given two inequalities and check which point holds true.
A)
 (10,10)
Putting this point in the second inequality we have:

which is not true.
Hence, Option: A is incorrect.
B)
 (10,-5)
Putting this point in first inequality we have:
 

which is not true.
Hence, option: B is not true.
C)
 (2,10)
Putting this point in second inequality we have:
 

which is not true.
Hence, Option: C is incorrect.
D)
 (10,1)
Putting this point in first inequality we have:

which is true.
Putting this point in second inequality we have:

which is again true.
Hence, (10,1) is a possible solution to the system of inequalities.