<PRE><B>Question 92075</B>
the perimeter (2L+2W) is 30 ... 2(L+W)=30 ... L+W=15 ... L=15-W ... so the area is A=(L)(W) ... A=(15-W)(W) ... A=15W-W^2


the maximum value for A occurs on the axis of symmetry of the graph


the equation of the axis of symmetry for ax^2+bx+c is x=-b/2a


in this case W=-15/2(-1) or W=7.5 ... since L+W=15, L=7.5


the rectangle of perimeter 30 with the greatest area is a square with side 7.5</PRE>