Find the equation of the line parallel to the $y-$ axis and passing through the point of intersection of the lines $x-7y+5=0$ and $3x+y=0$.

(N/A) The equation of any line parallel to the $y-$ axis is of the form $x=a$ $(1)$.
The two given lines are $x-7y+5=0$ $(2)$ and $3x+y=0$ $(3)$.
From equation $(3)$,we get $y = -3x$.
Substituting $y = -3x$ into equation $(2)$:
$x - 7(-3x) + 5 = 0$
$x + 21x + 5 = 0$
$22x = -5$
$x = -\frac{5}{22}$.
Since the line $x=a$ passes through the point of intersection,the value of $a$ is the $x-$ coordinate of the intersection point.
Therefore,the required equation of the line is $x = -\frac{5}{22}$ or $22x + 5 = 0$.