Find the dimensions of a rectangle with a perimeter of 54 meters, if it's length is 3 meters less than twice it's width?

Question

 Find the dimensions of a rectangle with a perimeter of 54 meters, if it's length is 3 meters less than twice it's width

Answer 1

Let L = length

Let W = width

 

L = 2W - 3, since the length is 3 meters less than twice the width

 

The formula for perimeter is P = W + L + W + L = 2W + 2L

 

So 2W + 2L = 54

 

Substitute the value for L from the 1st equation in to the 2nd equation to get 

 

2W + 2(2W - 3) = 54

2W + 4W - 6 = 54

6W = 60

W = 10

 

So L = 2W - 3 = 2(10) - 3 = 20 - 3 = 17

 

The width is 10 meters and the length is 17 meters.