Question 1073768
Let n be the width of the rectangle.  Then its length is n+40. So:
n(n+40)=1200
n²+40n-1200=0
(n+60)(n-20)=0
n=-60 or 20
The width of the rectangle is 20 cm.; its length is 60 cm. &#9786;&#9786;&#9786;&#9786;