Sabendo que x2 + y2=74 e que xy=35, calcule valor de (x - y2)2

To solve this problem you must apply the proccedure shown below:

 1. You have the following information given in the problem above:

 - x²+y²=74
 xy=35

 2. Therefore, you have that (x-y)² is:

 =(x-y)²
 =x²-2xy+y²
 =(x²+y²)-2xy

 3. When you substitute the values given in the problem, you obtain:

 =74-2(35)
 =74-70
 =4

 4. Therefore, as you can see, the correct answer is: 4