Đáp án:
$\begin{array}{l}
10)\\
a)O\left( {0;0} \right) \in \left( 1 \right)\\
\Rightarrow 0 = \left( {k + 1} \right).0 + k\\
\Rightarrow k = 0\\
b)\left( {0;1 - \sqrt 2 } \right) \in \left( 1 \right)\\
\Rightarrow 1 - \sqrt 2 = \left( {k + 1} \right).0 + k\\
\Rightarrow k = 1 - \sqrt 2 \\
c)\left( 1 \right)//y = \left( {\sqrt 3 + 1} \right).x + 3\\
\Rightarrow \left\{ \begin{array}{l}
k + 1 = \sqrt 3 + 1\\
k \ne 3
\end{array} \right.\\
\Rightarrow \left\{ \begin{array}{l}
k = \sqrt 3 \\
k \ne 3
\end{array} \right.\\
\Rightarrow k = \sqrt 3 \\
11)\\
a)Khi:x = 2\\
\Rightarrow y = 2x - 1 = 2.2 - 1 = 3\\
\Rightarrow \left( {2;3} \right) \in y = a.x - 4\\
\Rightarrow 3 = a.2 - 4\\
\Rightarrow a = \frac{7}{2}\\
b)Khi:y = 5\\
\Rightarrow y = - 3x + 2 = 5\\
\Rightarrow x = - 1\\
\Rightarrow \left( { - 1;5} \right) \in y = a.x - 4\\
\Rightarrow 5 = a.\left( { - 1} \right) - 4\\
\Rightarrow a = - 9
\end{array}$
