If $$ {xy over x+y}= a, $$ $${xz over x+z}=b $$ and $$ {yz over y+z} =c $$ where a, b, c are all non zero numbers, then x equals to

If $$ {xy over x+y}= a, $$ $${xz over x+z}=b $$ and $$ {yz over y+z}

1.	If $$ {xy over x+y}= a, $$ $${xz over x+z}=b $$ and $$ {yz over y+z} =c $$ where a, b, c are all non zero numbers, then x equals to
A.	$$ 2abc over {ab+bc-ac} $$
B.	$$ 2abc over {ab+ac-ac} $$
C.	$$ 2abc over {ac+bc-ab} $$
D.	$$ 2abc over {ac+bc-ac} $$
Answer» D. $$ 2abc over {ac+bc-ac} $$