Tina brought some nail polish and lip gloss at the store. the nail polish costs $4.50 per bottle and lip gloss costs $7 per tube. tina brought 9 items and spent $50.50.how many of each item did she buy

The price of a dozen eggs was $1.63. suppose the price increases m dollars per dozen and then the price decreases $0.12 per dozen. which expression represents the current price of eggs after the two price changes?