If you have worked steadily through the Programme, you should have no difficulty with this exercise. Take your time and work carefully. There is no extra credit for speed. Off you go then. They are all quite straightforward.
Find the values of $k$ for which the following equations are consistent:
$$
\left\{\begin{array}{c}
3 x+5 y+k=0 \\
2 x+y-5=0 \\
(k+1) x+2 y-10=0
\end{array}\right.
$$