Length of the common chord of the parabola y2=8x and the circle  x2+y2−2x−4y=0 is

Any point on the parabola is 2t2,4t which lies onthe circle if t4+3t2−4t=0⇒t=0,1⇒end points of the common chord are (0, 0) and(2, 4) and the required length is 25.