\(|a + b + c - 2x| + \sqrt{(x^2 - a - b - c)^2} =-|c| \)
As we are adding an absolute value and a positive radical value, \(-|c|\) cannot be negative number and must be \(0\).
Plugging in \(c = 0\) into the original equation leaves:
\(|a + b - 2x| + \sqrt{(x^2 - a - b)^2} = 0 \)
As this sum comes to \(0\), both \(|a + b - 2x|\) and \(\sqrt{(x^2 - a - b)^2}\) are equal to \(0\) and therefore equal to one another. This also means that \(|a + b - 2x| = a + b - 2x\) as zero is neither negative nor positive, and that \(\sqrt{(x^2 - a - b)^2} = x^2 - a - b\) as the square and squareroot of zero will always be zero.
Letting them equal one another:
\(a + b - 2x = x^2 - a - b \)
\(2a + 2b = x^2 + 2x\)
\(2(a+b) = x(x+2)\)
From this one can deduce that \(x = 2\), that \(a = x = 2\) and that \(b = 2\)
If one plugs these values, as well as \(c = 0\), back into \(|a + b + c - 2x| + \sqrt{(x^2 - a - b - c)^2} =-|c| \) one will get: \(|2+2+0 - 4| + \sqrt{(2^2 - 2 - 2 - 0)^2} = 0\) which holds.
Therefore, \(x + c = 2\)
ANSWER C