The angle between the lines `y=x` and `y=-x+6` is

The angle between the lines x = 10 and y = 10 is "_______" .

The obtuse angle between the lines y=-2xand y=x+2 is

The angle between the lines 2x+y+4=0 and y-3x=7 is

What is the angle between the lines x+y=1 and x-y=1 ?

If the point (1+cos theta,sin theta) lies between the region corresponding to the acute angle between the lines 3y=x and 6y=x, then

The angle between the lines 2x=3y=-z and 6x=-y=-4z is