The correct answer to your question is 15 days because if she drinks 1/3 of a can a day it will take 3 days to drink one can. Now multiple the 3 days for one can by the 5 cans and you get 15 days to finish all of the cans.
Simplifying
18x + -44 = 13y + -38
Reorder the terms:
-44 + 18x = 13y + -38
Reorder the terms:
-44 + 18x = -38 + 13y
Solving
-44 + 18x = -38 + 13y
Solving for variable 'x'.
Move all terms containing x to the left, all other terms to the right.
Add '44' to each side of the equation.
-44 + 44 + 18x = -38 + 44 + 13y
Combine like terms: -44 + 44 = 0
0 + 18x = -38 + 44 + 13y
18x = -38 + 44 + 13y
Combine like terms: -38 + 44 = 6
18x = 6 + 13y
Divide each side by '18'.
x = 0.3333333333 + 0.7222222222y
Simplifying
x = 0.3333333333 + 0.7222222222y