$$ \begin{align*} \textbf{Find the value of } \\&\ \left( 1 a-b\right)^2 + \left(b- 2 \right)^2 + \left( - 6 c - 1 \right)^2 = 0 \\&\ \left( 7 a-b\right)^2 + \left(b- 8 \right)^2 + \left( - 12 c - 9 \right)^2 = 0 \\&\ \left( 1 a-b\right)^2 + \left(b- 14 \right)^2 + \left( - 9 c - 9 \right)^2 = 0 \\&\ \text { where a, b and c are real numbers. } \\&\ \end{align*} $$