Questions in st-line

Select	Question
	The angle between the lines $xy=0$ is equal to
	The line passing through the points (3, – 4) and (–2, 6) and a line passing through (–3,6) and (9, –18) are
	If the line $2x+3ay-1=0$ and $3x+4y+1=0$ are mutually perpendicular, then the value of a will be
	A straight line through origin bisect the line passing through the given points $(a\cos \alpha ,a\sin \alpha )$ and $(a\cos \beta ,a\sin \beta )$ , then the lines are
	The lines ${{a}_{1}}x+{{b}_{1}}y+{{c}_{1}}=0$ and ${{a}_{2}}x+{{b}_{2}}y+{{c}_{2}}=0$ are perpendicular to each other, if
	The lines $y=2x$ and $x=-2y$ are
	If the line passing through (4, 3) and (2, k) is perpendicular to $y=2x+3$ , then $k =$
	The number of straight lines which is equally inclined to both the axes is
	The equation of the bisector of the acute angle between the lines $3x-4y+7=0$ and $12x+5y-2=0$ is
	The equation of the line which bisects the obtuse angle between the lines $x-2y+4=0$ and $4x-3y+2=0$ , is