Two circles intersect at A and B. A common external tangent is tangent to the circles at T and U as shown. Let M be the intersection of line AB and TU. If AB = 9 and BM = 3 find TU.
thanks to anyone who answers! :)
~ iamhappy
Consider the power of point M with respect to each of the circles.
MT2=MU2=MB⋅MA=3⋅12=36
This implies MT=MU=6
Therefore, TU=MT+MU=6+6=12
+569 
