Answer:
b = 7 inches and l = 12 inches
Step-by-step explanation:
Given that,
The area of a rectangle, A = 84 sq inches
Let the width is b.
Length = (5+b)
The area of a rectangle is given by :
A = lb
So,
[tex]84=b\times (5+b)\\\\b^2+5b-84=0\\\\(b-7)(b+12)=0\\\\b=7\ in, b =-12\ in[/tex]
Neglecting negative value,
b = 7 inches
Length, l = 5+b = 5+7
l = 12 inches