The length of a rectangular piece of steel in a bridge is 3 meters less then double the width. The perimeter of the piece of steel is 24 meters Find the length and width of the piece of steel.

Question

The length of a rectangular piece of steel  in a bridge is 3 meters less then double the width. The perimeter of the piece of steel is 24 meters Find the length and width of the piece of steel.

l=3-2w? is part of the formula?

Reiny · Answer

Your definition of L is opposite of what it should be

L = 2W - 3

now use your definition of perimeter to solve

Perimeter of a rectange = 2W + 2L
2W + 2(2W-3) = 24
2W + 4W - 6 = 24
6W = 30
W = 5

then L = 2(5)-3 = 7

Your rectangle is 5 by 7
check:
P = 2(5)( + 2(7) = 10+14 = 24

Christopher · Answer

Oh I got the formula backwards just had to flip it around. So yeah I got L= 7 for the length of the piece of steel and W=5 for the width of the piece of steel. I checked it and I got the same answer.