Answer:
4 units
Step-by-step explanation:
Let the width be w and length be l
w=l-1 --------(1)
Area=w*l
lw=20 --------(2)
Putting eq 1 in 2
l(l-1)=20
l²-l-20=0
l²-5l+4l-20=0
l(l-5)+4(l-5)=0
(l+4)(l-5)=0
Either
l+4=0 OR l-5=0
l=-4. OR. l=5
(Contrary to be given to l=-4as it is negative hence l=length =5)
Now putting l in (1)
w=5-1
w=4 units
