Question 769520
Can someone please help?

Expand (x-2√y)(x+2√y) and simplify.  Assume y ≥ 0
A.  x^2-4x√y+y
B.  x^2-4x√y+y
C.  x^2+4y
D.  x^2-4y

I got C?  (x-2√y)(x+2√y)= x^2-2x√y-2x√y-4√y^2= x^2-4√y^2= x^2+4√y+y
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All the symbols are not appreciated.  You're wasting your time and mine.
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It's the product of a sum and difference.
{{{(a-b)*(a+b) = a^2 - b^2}}}
{{{(x - 2sqrt(y))*(x + 2sqrt(y)) = x^2 - 4y}}}