SOLUTION: The perimeter of a rectangular room is 120 feet. The sum of four times the width and three times the length is 204 feet. Find the length and the width of the room. I just can't fi

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Question 627499: The perimeter of a rectangular room is 120 feet. The sum of four times the width and three times the length is 204 feet. Find the length and the width of the room.
I just can't figure out how I would go about solving this problem. I have tried a few different ways and it does not look like i know what I am doing. I know i got to do it as P=W+L. But thats as far as i get. P being 120 feet= 4W+3L

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
You are mistaken about perimeter.
Remember that in a rectangle, there are:
2 long sides plus
2 short sides which gives me
4 sides total
So the formula for perimeter is
+P+=+2L+%2B+2W+
You are given +P+=+120+ ft
+120+=+2L+%2B+2W+
Divide through by 2
(1) +60+=+L+%2B+W+
also
(2) +4W+%2B+3L+=+204+
-------------------------
(1) +W+=+60+-+L+
Substitute (1) into (2)
(2) +4%2A%28+60+-+L+%29+%2B+3L+=+204+
(2) +240+-+4L+%2B+3L+=+204+
(2) +-L+=+-36+
(2) +L+=+36+
and, since
(1) +W+=+60+-+L+
(1) +W+=+60+-+36+
(1) +W+=+24+
The length is 36 ft
The width is 24 ft
check:
(2) +4W+%2B+3L+=+204+
(2) +4%2A24+%2B+3%2A36+=+204+
(2) +96+%2B+108+=+204+
(2) +204+=+204+
OK