Question 995689
Take width as x, and since length is 20 longer than width, length should be (x+20). 
Perimeter=140
140=2(x+20)+2x
140=2x+40+2x
140=4x+40
140-40=4x
100=4x
x=25
Width=25
Length
=25+20
=45
Area
=Width×Length
=25(45)
=1125m²