Question 311990
Let l be the legnth of the rectangle, w be the width of the rectangle.
The perimeter of a rectangle is 
{{{P=2*(l+w)=120}}}
1.{{{l+w=60}}}
The area of a rectanlge is
{{{A=l*w}}}
2.{{{l*w=900}}}
From eq. 2,
{{{l=900/w}}}
Substitute into eq. 1,
{{{l+w=60}}}
{{{900/w+w=60}}}
{{{900+w^2=60w}}}
{{{w^2-60w+900=0}}}
{{{(w-30)^2=0}}}
{{{w-30=0}}}
{{{w=30}}}
Then from eq. 2,
{{{l=30}}}
The orchard is a 30 yd x 30 yd square.