SOLUTION: the perimeter of a rectangle is 90m. the length is 6m longer than twice the width. what is the length and width?

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Question 297022: the perimeter of a rectangle is 90m. the length is 6m longer than twice the width. what is the length and width?
Answer by Deina(147) About Me  (Show Source):
You can put this solution on YOUR website!
Variables Used

  • p = perimeter

  • l = length

  • w = width


What do we know? We know that:
p = 90m
l = 2w + 6
and finally we know that
p = 2(l + w) or 2l + 2w

so we will substitute 2w + 6 for l in the formula:
p = 2(2w + 6) + 2w
Now we will distribute:
p = 4w + 12 + 2w
combine like terms:
p = 6w + 12
I like working on the left, so we'll flip-flop (advanced mathematical term) and replace "p" with 90:
6w + 12 = 90

subtract 12 from each side:
6w = 78
divide each side by 6:
+cross%286%29w%2Fcross%286%29+=+78%2F6+=+13+ so
w = 13
now remember that l = 2w + 6, and substitute 13 for 'w'
+l+=+cross%282%2813%29%29+26+%2B+6+=+32+
l = 32.
Your answers are
Length = 32m
Width = 13m & bob's your uncle!