Answer:
The cost of one granola bar is 
The cost of one bottle of water is 
Step-by-step explanation:
Let
x------> the cost of one granola bar
y-----> the cost of one bottle of water
we know that
-----> equation A
-----> equation B
using a graphing tool
Solve the system of equations
Remember that
The solution of the system of equations is equal to the intersection point both graphs
The intersection point is 
see the attached figure
therefore
The cost of one granola bar is 
The cost of one bottle of water is 