Frank wants to build a garden with the dimensions below.

if the garden has an area of 91ft2, what are the dimensions of the garden?
feet wide by feet long..

frank decides to put a fence around the garden. how many feet of fencing does he need to buy?
feet

Given:
Length = x + x + 3 = 2x + 3
Width = 2 + x 

Area = length * width 
91 ft² = (2x + 3) (2+x)
91 = 4x + 2x² + 6 + 3x
0 = 2x² + 7x + 6 - 91
0 = 2x² + 7x - 85

(2x + 17) ( x - 5)

x = -17/2 or  x = 5

Let x = 5 ; 

length = 2x + 3 = 2(5) + 3 = 13
width = 2 + x = 2 + 5 = 7

 Area = 13 x 7 = 91

Perimeter = 2(length + width)
Perimeter = 2(13 + 7)
Perimeter = 2(20)
Perimeter = 20 feet of fencing