21. 0.25x - 1.25 - 3x + 2 = -2.75x + 0.75
22. 15/100= 0.15. 0.15•64,000= 9,600. The answer is D.
23. 1,200-300= 9,000. 1,200+300= 15,000. 9,000/15,000= 3/5. 3/5= 0.6. 60% of the building is aboveground.
24. The patterson seems to be the y=18x and when you plug 7 in to the equation, you get 126, not 128, so D is the answer.