Application Of Derivatives

A poster is to be printed on a rectangular sheet of paper of area \(18 \mathrm{~m}^2\). The margins at the top and bottom of \(75 \mathrm{~cm}\) each and at the sides \(50 \mathrm{~cm}\) each are to be left. Then the dimensions i.e. height and breadth of the sheet, so that the space available for printing is maximum, are ________ respectively.