PLEASE help with one geometry question? this is the only one I don't understand!!!!!!

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Answer 1 · 2018-06-13T08:50:47

#color(blue)(14.49" in ")#2 d.p.

To solve this you need to use the property of a secant line and tangent.

enter image source here

From diagram:

#(AB)^2= CB*(DC+CB)#

So we have:

#(ST)^2=7*(23+7)=210#

#ST=sqrt(210)~~14.49137675#

#14.49" in "# 2 d.p.