Let length = l
width = w
Acc. to the question = l = w - 8
Area = 9 units
Area of a rectangle = w ( w - 8) = 9
= w² - 8w = 9
= w² - 8w - 9 = 0
= w² - 9w + w - 9
= w( w - 9 ) 1( w-9)
= (w + 1) ( w-9)
= w = -1, 9
= Since width cannot be equal to a negative value, w = 9 units
l = w - 8
l = 9 - 8
∴length = 1 unit