Try to construct an optimal area ABCD using fence of fixed length L.[br][br]1) Which choice of x gives maximum area ?[br]2) How can you find it ?[br]3) How much more area can you get using the wall ?[br]4) Can you think of a shape yielding a bigger area than a rectangle

Examine position of poles A,B,C and D in rectangle ABCD.[br][br]Lets start by assuming L is the length of the circumfering fence and thus[br][math]L = AB+BC+CD+DA[/math]; [math]x=AB=DC[/math] and [math] y=BC=DA [/math].[br][br]Tips:[br]- ABCD can be moved about with point A (looks like O ).[br]- Check [x] visualize to place ABCD on to the image.[br]- Toggle Trace ON/OFF with the button and clear with Ctrl-F.