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Solve for x a. 9 b. 14 c. 13 d. 11

Solve for x a. 9 b. 14 c. 13 d. 11-example-1
User KWA
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1 Answer

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We must remember one of the important properties of the secant lines to a circle.

If from a point outside the circle (Q) there are two secant lines that cross the circle at two points A and B for a secant line and C and D for another secant line, then the product of the segments of these two secant lines are equal to each other


AQ* BQ=CQ* DQ

Let's see the image given by the exercise with the notation of the property:

Applying the rule, we get,


\begin{gathered} 7(x+7)=6(15+6) \\ 7x+49=6(21) \\ 7x+49=126 \\ 7x=77 \\ x=(77)/(7)=11 \end{gathered}

In that sense, the correct answer is D. x= 11.

Solve for x a. 9 b. 14 c. 13 d. 11-example-1
User Ramon Canales
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