Community Answer

Soln{:[" Let Length \& breadth (width) of a "],[" rectangle are "xsy". "],[2(x+y)=30],[x-1y=(30)/(2)=15],[:.y=15-x-1],[" Area "A=xy],[A(x)=x(15-x)=15 x-x^(2)],[A^(')(x)=15-2x],[" For maxim'izing "A^(')(x)=0], ... See the full answer