The pair of straight lines joining the origin to the common points x2+y2=4 and y=3x+c are perpendicular if c2 =
The pair of straight lines joining the origin to the points of intersection of the line y=2√2x+c and the circle x2+y2=2 are at right angles, if
The equation of pair of straight lines joining the point of intersection of the curve x2+y2=4 and y - x = 2 to the origin, is