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# This one got me

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Help

Jan 26, 2019

### 6+0 Answers

#1
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there is formula for this, it is 9*(9+16) is the tangent line length squared, so 225=9x^2 so x=5.

HOPE THIS HELPED!

Jan 26, 2019
#4
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how did you get 9x^2?

Guest Jan 27, 2019
#2
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Since this has a tangent and secant, Power Of Point gives us \(9x^2=225, x^2=25, \boxed{x=5}.\)

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Jan 27, 2019
#3
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how did you get 9x^2?

Guest Jan 27, 2019
#5
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Tetre got it from (3x)^2 = 9x^2   Thanks Tertre and asdf

There is an obscure circle geometry  law that says if A is a point external to the circle

then the square of the tangential distance from A to the circle

is equal to the square of the distance from A to the furthest point on any chord that is collinear with A.

Maybe that can be worded better. :/

anyway it says     \((3x)^2=(9+16)^2\)

No one on this post has attempted to prove this.  They have simply used it to answer your question.

Melody  Jan 27, 2019
#6
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thanks

Guest Jan 27, 2019
edited by Guest  Jan 27, 2019