x=3 represents the amount of fabric required to make the shorts, since it says the company uses 82.5 yards of fabric to make shirts and shorts, so you have to add the amount of fabric each pair of shorts takes to create. hope this !
im pretty sure it is $660
45+10x = y
$45 -- stays the same no matter what so that's constant.
$10 -- this varies dependent on the number of vaccinations your dog needs, so you'd use a variable to represent the number of vaccinations (in this case i'm using variable "x").
so, for example if your dog needed 7 vaccinations, it would be: 45+10(7) = y -- answer being $115.