Determine matrix of linear map Linear map is given through:
$\phi\begin{pmatrix} 3 \\ -2 \end{pmatrix} =\begin{pmatrix} -3 \\ -14 \end{pmatrix} $
$\phi\begin{pmatrix} 3 \\ 0 \end{pmatrix} =\begin{pmatrix} -9 \\ -6 \end{pmatrix}$
Determine matrix $A$ linear map.
Here I have solution but I dont understand how to get it.
$A=\begin{pmatrix} -3 & -3 \\ -2 & 4 \end{pmatrix}  $

We note that when we are constructing a matrix for a linear map, we need to know the matrix related to which basis. Here, if you consider the vectors 
$\begin{pmatrix} 3 \\ -2 \end{pmatrix}$ and $\begin{pmatrix} 3 \\ 0 \end{pmatrix}$ 
as the basis of your vector space, the given matrix by you is not the correct one. Actually, as we have
$$\phi\begin{pmatrix} 3 \\ -2 \end{pmatrix} =\begin{pmatrix} -3 \\ -14 \end{pmatrix}=7\times \begin{pmatrix} 3 \\ -2 \end{pmatrix}-8\times \begin{pmatrix} 3 \\ 0 \end{pmatrix}$$
$$\phi\begin{pmatrix} 3 \\ 0 \end{pmatrix} =\begin{pmatrix} -9 \\ -6 \end{pmatrix}=3\times \begin{pmatrix} 3 \\ -2 \end{pmatrix}-6\times \begin{pmatrix} 3 \\ 0 \end{pmatrix}$$
The matrix should be (according to this basis!)
$$A=\begin{pmatrix} 7 & 3 \\ -8 & -6 \end{pmatrix}$$
Perhaps your given matrix is related to another basis.
