For what value of $a$ are the lines $x = 3$,$y = 4$,and $4x - 3y + a = 0$ concurrent?

Let $a, b, c$ and $d$ be non-zero numbers. If the point of intersection of the lines $4ax + 2ay + c = 0$ and $5bx + 2by + d = 0$ lies in the fourth quadrant and is equidistant from the two axes,then:

If the lines $x + q = 0$,$y - 2 = 0$,and $3x + 2y + 5 = 0$ are concurrent,then the value of $q$ is:

The equation of the straight line joining the point $(a, b)$ to the point of intersection of the lines $\frac{x}{a} + \frac{y}{b} = 1$ and $\frac{x}{b} + \frac{y}{a} = 1$ is

The line on which the lines $ax + by = 1$ and $bx + ay = 1$ (with $a \neq 0 \neq b$) intersect for any real values of $a$ and $b$ is

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 $3x+y=0$.