How to change 12x12units square shape into 9x16 units rectangle shape & vice versa, in 4 cut pieces?

Question

Explain it in words. if theres any picture, it would be better.
thanx

Answer 1

I asked this question before by max 2 cut pieces, found people taking answers from websites.
so I did not enjoy the answers.

cut the 12x12sq into 9x12, and three piecec of 3x4
put the put on one side of 9 all three 3x4 vertically
you will get 9x16

Answer 2

In a 12 by 9 rectangle you carve out a rectangle of size 8 by x where x has to be determined. The remainder will be piece A and another one identical will be piece B. If you put them together you can get a 16 by 9 rectangle with a hole in it, or a 12 by (9+9-x) rectangle, with a hole in it. Let's choose x= 6 and look at the holes. On one case it's a 3 by 8 rectangle, and in the other it's a 6 by 4 rectangle. So with 2 rectangles of size 3 by 4, you are done.