I saw this question on Math group and tried to solve it question to no avail. I approached it by taking the square of the first row, adding it to the second, then subtracting the fourth row from the result to get third row as answer, but I couldn't make any connection between the rows. Each time I try to make one but it doesn't suit for other columns. These questions belong to YÖS exam and I think the book is YÖS questions by Kuark publications. Thanks.