The length of a rectangle is one less than 3 times the width. Draw a picture of the rectangle and then find the dimensions of the rectangle if the perimeter is 54 mm?

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the length of a rectangle is one less than 3 times the width. Draw a picture of the rectangle and then find the dimensions of the rectangle if the perimeter is 54 mm?

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Answer 1 · 2018-04-15T17:07:25

length #= 20#

width #= 7#

"The length of a rectangle is one less than 3 times the width."

which means:

#L= 3w-1#

So we add up the lengths and the widths and set them #=# to #54# (the perimeter).

#w + w + 3w -1 + 3w -1 = 54#

#8w-2 = 54#

#8w = 56#

#w = 7#

We plug that into #L = 3w-1#:

#L = 3(7)-1#

#L = 21-1#

#L = 20#