Answer:
G. 8
Explanation:
Let point X be the point where the chords intersect. For a given point of intersection, the product of the distances from that point to the circle is a constant. Here, that means ...
XA·XB = XC·XD
3x = 4·6 . . . . substitute the given values
x = 24/3 . . . . divide by the coefficient of x
x = 8
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This is a property of chords (and secants). The same relationship is true even if point X is outside the circle: the product of distances to the two intersection points with the circle is a constant.