Which number best represents a debt of $9,799?

Really need on these. i have no idea what to do

Marquise has 200 meters of fencing to build a rectangular garden. the garden's area (in square meters) as a function of the garden's width w w (in meters) is modeled by: a ( w ) = − w 2 + 1 0 0 w a(w)=−w 2 +100w what side width will produce the maximum garden area? meters

What is the value of n in the equation -1/2(2n+4)+6=-9+4(2n+1)