Answer:
Width=25 ft and length=30 ft
Explanation:
In order to find the answer let's remember that the area (A) of a rectangle is:

Let's assume that the length of the room is 'X' feet.
Becuase the problem mentioned that the width (Y) of the room is 5 feet less than the length, then:

Now, using the area equation we have:
A=width*length
but using the width expression we have:


Using the root's equation we have:




Because the length (X) can't be negative, then length=30 feet. In order to find the width we have:



So the width is 25 feet.
In conclusion the room has a width=25 ft and length=30 ft.