Question

In circle D, the radius DA is 9 mm and the tangent line AB = 12 mm.
Find DB

Answer 1

DB is 15 mm

Explanation:

Due to pythagoras theorem

`db ^(2) = da ^(2) + ab ^(2)`

`db {}^(2) = 9 {}^(2) + 12 {}^(2)`

`db = √(225)`

db=15