If x ¤ y = (x + y)^2 - (x - y)^2. Then √7 ¤ √7 =  Pick one: A) 0 B) 5 C) 10 D) 15 E) 28
X = √7 and Y also =√7   Applying the function (√7+√7)^2 - (√7-√7)^2 = (2√7)^2 - 0 = 4 x 7 = 28.   Note: Alternative Approach is the entire function is represented as X^2 - Y^2 = (X+Y)(X-Y) which can be simplified as (x+y+x-y)(x+y-(x-y)) = (2x)(2y)=4xy. Substituting x=√7 and y = √7 you get the answer 28.   Answer 28
<result>E</result>
If x ¤ y = (x + y)^2 - (x - y)^2. Then √7 ¤ √7 =