it seems not to work out for me :S
Can someone work it out and tell me what the got since I know the right answer (back of the book) but I'm not sure if I am doing something wrong or if it's an mestake in the book.

Regards

This post was edited by Marcelpro on May 26 2014 03:14am

Area of Rectangle A = Length x Width = (6x + 3) (3x + 1) = 18x^2 + 15x + 3

Area of Rectable B = Length x Width = 5x (4x + 2) = 20x^2 + 10x

If the areas are equal,

18x^2 + 15x + 3 = 20x^2 + 10x

The above equation can be written as

2x^2 - 5x - 3 = 0

Solving the quadratic equation,

2x^2 - 6x + x - 3 = 0
2x(x - 3) + 1 (x - 3) = 0
(x - 3) (2x +1) = 0

This gives us two possible values for x. Either x = 3 or x = -1/2. However, since the side of a rectangle cannot be negative, x = 3.

I got the answer later on today aswell I made a mestake in multiplying for some reason i said (5x)(4x) = 20x and thats why i wasnt getting the right answer.
Thanks anyway

This post was edited by Marcelpro on May 26 2014 12:04pm