$\begin{array}{l}
M \in y'Oy \Rightarrow M\left( {0;\,\,m} \right)\\
Pt\,\,AB:\,\,\,\frac{{x + 2}}{{4 + 2}} = \frac{{y + 3}}{{7 + 3}}\\
\Leftrightarrow 10\left( {x + 2} \right) = 6\left( {y + 3} \right)\\
\Leftrightarrow 5x + 10 = 3y + 9\\
\Leftrightarrow 5x - 3y + 1 = 0\\
M,\,\,A,\,\,B\,\,\,thang\,\,hang\\
\Rightarrow M \in AB\\
\Rightarrow 5.0 - 3.m + 1 = 0\\
\Leftrightarrow 3m = 1\\
\Leftrightarrow m = \frac{1}{3}\\
\Rightarrow M\left( {0;\,\,\,\frac{1}{3}} \right).
\end{array}$
