Let XY be a tangent to a circle, and let be a XBA secant of the circle, as shown below. If AX = 16 and XY = 8, then what is AB?

Let XY be a tangent to a circle, and let be an XBA secant of the circle, as shown below. If AX = 16 and XY = 8, then what is AB?

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XY^{2} = XB * AX

8^{2} = XB * 16

XB = 4 AB = 12

I think the answer is 9.6