Set the width to be x. Thus, the length is 4x.
The perimeter is 2(x+4x)=100, so x=10.
Plugging in x=10, you get that 4x=40.
So, the area of the rectangle is 400 [tex]m^2[/tex].
Because there are 100 centimeters in a meter and you are asking for area, you must multiply by [tex]100^2[/tex] to get 4000000 [tex]cm^2[/tex].
