$\{\begin{array}{l}x=\frac{16}{5}=3\frac{1}{5}\\ y=-\frac{13}{5}=-2\frac{3}{5}\end{array}\vee \{\begin{array}{l}x=-1\\ y=-2\end{array}$
Współrzędne punktów $A$ i $B$: $A=\left(3\frac{1}{5},-2\frac{3}{5}\right)$, $B=\left(-1,-2\right)$.
Znajdziemy teraz współrzędne $M$, wykorzystując: $\overrightarrow{AM}=-2\cdot \overrightarrow{BM}$. Niech $M=\left(x_M,y_M\right)$.
$\overrightarrow{AM}=\left[x_M-3\frac{1}{5},y_M+2\frac{3}{5}\right]$
$-2\cdot \overrightarrow{BM}=-2\cdot \left[x_M+1,y_M+2\right]=\left[-2\left(x_M+1\right),-2\left(y_M+2\right)\right]=\left[-2x_M-2,-2y_M-4\right]$
$\left[x_M-3\frac{1}{5},y_M+2\frac{3}{5}\right]=\left[-2x_M-2,-2y_M-4\right]$
$x_M-3\frac{1}{5}=-2x_M-2\wedge y_M+2\frac{3}{5}=-2y_M-4$
$3x_M=\frac{6}{5}|:33y_M=-6\frac{3}{5}|:3$
$x_M=\frac{6}{5}\cdot \frac{1}{3}=\frac{2}{5}{y}_M=-\frac{33}{5}\cdot \frac{1}{3}=-\frac{11}{5}=-2\frac{1}{5}$ 
$M=\left(\frac{2}{5},-2\frac{1}{5}\right)$               
Odp.: $A=\left(3\frac{1}{5},-2\frac{3}{5}\right)$, $B=\left(-1,-2\right)$, $M=\left(\frac{2}{5},-2\frac{1}{5}\right)$.