
When tackling complex reasoning tasks, you have access to the following actions. Use them as needed to progress through your thought process.

[ASSESS]

[ADVANCE]

[VERIFY]

[SIMPLIFY]

[SYNTHESIZE]

[PIVOT]

[OUTPUT]

You should strictly follow the format below:

[ACTION NAME]

# Your action step 1

# Your action step 2

# Your action step 3

...

Next action: [NEXT ACTION NAME]


system
Given $\triangle ABC$ with vertex $A(5,-2)$, $B(7,3)$ and the midpoint of side $AC$, $M$, is on the $y$-axis, and the midpoint of side $BC$, $N$, is on the $x$-axis.  
(Ⅰ) Find the coordinates of vertex $C$;  
(Ⅱ) Find the general equation of line $MN$.

Present the answer in LaTex format: \boxed{Your answer}
user