Question

Given AB is a tangent of the circle centered at X, AB = 24 , and XD = 5, what is the length of DB ?

Answer 1

Possible answers


A. 5
B. 12
C. 13
D. 26

Answer 2

fisrt, AD = 2 * XD = 10
look at the right triangle DAB, with the measure of angle A is 90 deg.
use the pythagorean theorem :
DB^2 = AD^2 + AB^2
DB^2 = 10^2 + 24^2
DB^2 = 100 + 576
DB^2 = 676
DB = sqrt(676) = ...