Answer:
$5.25
Step-by-step explanation:
The two purchases can be described by the equations ...
3s +2p = 29.75
4s +3p = 42.00
If you multiply the first equation by 3 and subtract 2 times the second equation, the cost of a shirt pops out.
3(3s +2p) -2(4s +3p) = 3(29.75) -2(42.00)
9s +6p -8s -6p = 89.25 -84.00 . . . . . . . eliminate parentheses
s = 5.25 . . . . . . . . . . collect terms
One shirt costs $5.25.
