If real numbers x and y satisfy X & sup2; + 4Y & sup2; + 2x-8y + 5 = 0, then the value of X + y is equal to?

Split 5 into 1 + 4
(x²+2x+1)+(4y²-8y+4)=0
(x²+2x+1)+4(y²-2y+1)=0
(x+1)²+4(y-1)²=0
If the square is greater than or equal to 0 and the sum is 0, then both squares are equal to 0
So x + 1 = 0, Y-1 = 0
x=-1,y=1
x+y=0

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