Given line equation of 2-order:
$$2 x^{2} - 2 y^{2} - 8 \sqrt{2} y = 0$$
This equation looks like:
$$a_{11} x^{2} + 2 a_{12} x y + 2 a_{13} x + a_{22} y^{2} + 2 a_{23} y + a_{33} = 0$$
where
$$a_{11} = 2$$
$$a_{12} = 0$$
$$a_{13} = 0$$
$$a_{22} = -2$$
$$a_{23} = - 4 \sqrt{2}$$
$$a_{33} = 0$$
To calculate the determinant
$$\Delta = \left|\begin{matrix}a_{11} & a_{12}\\a_{12} & a_{22}\end{matrix}\right|$$
or, substitute
$$\Delta = \left|\begin{matrix}2 & 0\\0 & -2\end{matrix}\right|$$
$$\Delta = -4$$
Because
$$\Delta$$
is not equal to 0, then
find the center of the canonical coordinate system. To do it, solve the system of equations
$$a_{11} x_{0} + a_{12} y_{0} + a_{13} = 0$$
$$a_{12} x_{0} + a_{22} y_{0} + a_{23} = 0$$
substitute coefficients
$$2 x_{0} = 0$$
$$- 2 y_{0} - 4 \sqrt{2} = 0$$
then
$$x_{0} = 0$$
$$y_{0} = - 2 \sqrt{2}$$
Thus, we have the equation in the coordinate system O'x'y'
$$a'_{33} + a_{11} x'^{2} + 2 a_{12} x' y' + a_{22} y'^{2} = 0$$
where
$$a'_{33} = a_{13} x_{0} + a_{23} y_{0} + a_{33}$$
or
$$a'_{33} = - 4 \sqrt{2} y_{0}$$
$$a'_{33} = 16$$
then equation turns into
$$2 x'^{2} - 2 y'^{2} + 16 = 0$$
Given equation is hyperbole
$$\frac{\tilde x^{2}}{8} - \frac{\tilde y^{2}}{8} = -1$$
- reduced to canonical form
The center of canonical coordinate system at point O
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(0, -2*\/ 2 )
Basis of the canonical coordinate system
$$\vec e_1 = \left( 1, \ 0\right)$$
$$\vec e_2 = \left( 0, \ 1\right)$$