SOLUTION: The formula for the perimeter of a rectangle is P=2l,+ 2w, where l is the length and w is the width. A rectangle has a perimeter of 24 inches. Find its dimensions of it length is 3

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Question 994517: The formula for the perimeter of a rectangle is P=2l,+ 2w, where l is the length and w is the width. A rectangle has a perimeter of 24 inches. Find its dimensions of it length is 3 inches greater than its width.
Found 2 solutions by josgarithmetic, macston:
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Your perimeter formula looks like "P is twenty-one plus two w".

Use a better variable.
cross%28P=21%2B2w%29
P=2L%2B2w

Description and question give you this:
system%28L=3%2Bw%2CP=24%2CP=2L%2B2w%29
and just a couple of substitutions will give you a way to first solve for w.


STEPS
2L%2B2w=24
2%28w%2B3%29%2B2w=24
2w%2B6%2B2w=24
4w%2B6=24
4w=18
w=18%2F4=9%2F2=highlight%284%261%2F2%29, the width

Answer by macston(5194) About Me  (Show Source):
You can put this solution on YOUR website!
.
W=width; L=length=W+3in
.
P=2L+2W
P=2(L+W)
24in=2(L+W)
12in=L+W
12in=(W+3in)+W
12in=2W+3in
9in=2W
4.5in=W
ANSWER 1: The width is 4.5 inches.
.
L=W+3in=4.5in+3in=7.5in
ANSWER 2: The length is 7.5 inches.
.
CHECK:
P=2L+2W
24in=2(7.5in)+2(4.5in)
24in=15in+9in
24in=24in