If you have a graphing calculator just put in the equation in 'y=' (not the i equation), and then go to 2nd trace and see where the y=0, those numbers under the x column are the zeros. For the first one, the zeros are: -1, .5, and 2.8. For the second question the zeros are: -3 and about 1.9. The zeros with a decimal are estimations.
Use the are formula for a rectangle which is Length times Width to find the amount of square feet of carpeting.(16 times 14=224ft^2) Then you need multiply 224 by 12 because you have 224 square feet at $12 per square foot. So in the end it will cost $2688 to get the new carpet.