##### math help with math functions and circles

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Nov 1st, 2015

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If a secant segment and tangent segment are drawn to a circle from the same external point, the product of the length of the secant segment and its external part equals the square of the length of the tangent segment.

Therefore,

$\\ AB^2=AD\times AC\\ \\ 15^2=AD\times25\\ \\ 225=25 AD\\ \\ 25AD=225\\ \\ AD=\frac{225}{25}\\ \\$

$AD=9\hspace{5} mm$

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Nov 1st, 2015

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Nov 1st, 2015
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Nov 1st, 2015
Mar 24th, 2017
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