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?

Question

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?

10532 views around the world

You can reuse this answer
Creative Commons License

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#