The lines 3x -4y + 4 = 0 and 6x - By- 7 = 0 are tangents to the same circle. Then, its radius, is

Two given tangents are parallel to each other. Therefore, the distance between them is equal to the diameter of the circle.∴  Radius =12× Distance between 3x−4y+4=0 and 6x−8y−7=0⇒      Radius =124+729+16=34