Question

The the length of a tangent from a point a at a distance 5 cm from the centre of the circle is 4 cm find the radius of the circle ​

Answer 1

Step-by-step explanation:

this is the correct answer

Answer 2

Here, AB is the tangent that is drawn on the circle from a point A.

So, the radius OB will be perpendicular to AB i.e. OB ⊥ AB

We know, OA = 5cm and AB = 4 cm

Now, In △ABO,

OA2 =AB2+BO2 (Using Pythagoras theorem)

52 = 42+BO2

BO2 = 25-16

BO2 = 9

BO = 3

So, the radius of the given circle i.e. BO is 3 cm.