Answer:
16) 
17) y = -x - 4
18) y = -2x - 1
19) y = -2x
20)
Step-by-step explanation:
With the two points you find the slope using 
Then using that slope, plug the slope in with one of the points values of x and y into the point slope formula, and smiplify that into the y-intercept formula.
H=1/3+1/60d,d=R Hope this is correct.
0.62068966 or 18/29 depending on how you want to set it up.
22 because 6 inches on top and bottom means you need 12 inchesw each drape and you have 4 drapes so 48 inches therefor rounding that you get 1 yard each added onto the 8 feet and 5 feet for each drape.