System of Equations
Let:
x = cost of each notebook.
y = cost of each thumb drive.
Three notebooks and 2 thumb drives cost $43, thus:
3x + 2y = 43
Three notebooks and three thumb drives cost $57, thus:
3x + 3y = 57
Subtracting both equations:
3x - 3x + 3y - 2y = 57 - 43
Simplifying:
y = 14
Substituting into the first equation:
3x + 28 = 43
Subtracting 28:
3x = 15
Dividing by 3:
x = 5
Each notebook cost $5 and each thumb drive cost $14