Alright, lets get started.
Suppose the width of the garden is = x
And we know the fact that length of the rectangular garden to be 3 feet longer than its width.
So, the length will be =

So, the area of the garden will be =

area of the garden =

area of the garden =

The area specified for the garden is given 88 square feet. So

Subtracting 88 from both sides



Means
x = 8 or x = -11
Negative value of x is not possible, so
x = 8
Means width of the garden = 8 feet
So, length of the garden will be =
feet : Answer
Hope it will help :)