



 
Irvyn, You didn't say what the shape is but I expect it is a rectangle. Suppose that the rectangle is $x$ units long and $y$ units wide and that its perimeter is $P$ units and it has an area of $A$ square units. This gives the equations
and
Solve the first equation for $y,$ substitute into the second equation and solve the resulting quadratic for $x.$ Penny  


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