Answer:
Area(A) and perimeter(P) of rectangle is given by:


where,
l is the length and w is the width of the rectangle.
As per the statement:
A rectangular garden has a length that is modeled by the expression:
and a width(w) = 
A.
To find the area of the garden.
then;

Combine like terms;
square units.
Therefore, the area of the garden is,
square units.
B.
The owner of the garden wants to put a fence around the perimeter of the garden.
then;

Therefore, the perimeter of the garden is,
units