Finding the max area of a barn

Vhich expression is equivalent to 6(3x + 4)? 9x + 418 x + 2418x + 49x + 10 i might ! i really do hope u see this and answer it

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 x? enter your answer in the box.