Answer: the cost would be the same for 12 shirts.
Step-by-step explanation:
Let x represent the number of shirts for which the cost would be the same.
One company charges $9.65 per shirt plus a setup fee of $43. This means that total amount charged for x shirts would be
9.65x + 43
Another company charges $8.40 per shirt plus a $58 fee. This means that total amount charged for x shirts would be
8.4x + 58
For both costs to be the same, the number of shirts would be
9.65x + 43 = 8.4x + 58
9.65x - 8.4x = 58 - 43
1.25x = 15
x = 15/1.25 = 12
