Gaussian elimination
Given the system of equations
$$9 x - 14 y = - 39 x - 14 y$$
$$- a y + 2 x = - a y - 62 x$$
We give the system of equations to the canonical form
$$48 x = 0$$
$$64 x = 0$$
Rewrite the system of linear equations as the matrix form
$$\left[\begin{matrix}48 & 0\\64 & 0\end{matrix}\right]$$
It is almost ready, all we have to do is to find variables, solving the elementary equations:
$$48 x_{1} = 0$$
$$64 x_{1} = 0$$
We get the answer:
$$x_{1} = 0$$
$$x_{1} = 0$$