Question

need to find the perimeter of the box. the lenght of rectangular book is 2 unit less than its width. if the area of the book is 15 unit square.

Answer 1

Area is equal to length x height. Let us say that the height of the book is x, and then the length would be x-2.

Area = length x height
15 = (x-2)x
15= x^2 - 2x
0= x^2 -2x -15
x = 5
So the length would be (5-2)=3, and the height would be 5.

The overall perimeter would be 2xlength +2xheight so 6+10=16.