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

Find the equation of a straight line passing through the points (1, 3) and (-2, 4).

Find the equation of the straight line upon which the length of the perpendicular from the origin is 4√2 units and this perpendicular makes an angle of 75° with the positive direction of the x-axis.