Question

In the diagram shown, secants ADB and AEC have been drawn from external point A such that AD=6 AE=4 BD=8. Which of the following is the length of AC?

Answer 1

21

Explanation:

In the figure attached, the diagram is shown.

The following equation must be satisfied:

AB * AD = AC * AE

where the length of AB is:

AB = AD + DB

Combining the equations:

(AD + DB)* AD = AC * AE

Replacing with data:

(6 + 8)* 6 = AC * 4

AC = 84/4

AC = 21