Given:
The equation is:
Where c is the number of liters of carbonated water used.
To find:
How many liters of carbonated water did Louie use?
Solution:
We have,
We need to solve this equation for c to find the number of liters of carbonated water used by Louie.
Subtracting 4.2 from both sides, we get
Therefore, Louie used 3.9 liters of carbonated water.