Question 919119
x^2 + y^2 + 2x - 3= x^2 + y^2 -6x-3
8x = 0, x = 0  and y = ± √3
x = 0 the equation of the common chord
{{{drawing(300,300,   -6, 6, -6, 6,  blue(line(0,6,0,-6)) ,
 grid(1),
circle(1, 0,2),
circle(3,0,sqrt(12)),
circle(0, sqrt(3), 0.2),
circle(0, -sqrt(3), 0.2),
graph( 300, 300, -6, 6, -6, 6))}}}