Question

clarify my doubt....is it being taken randomly or what?!

Answer 1

When you have to find the distance between two points M(a,b) and N(c,d), You can assign (x1,y1) and (x2,y2) randomly to M and N.

That means

1. (a,b) can be (x1,y1) and (c,d) can be (x2,y2) or

2. (a,b) can be (x2,y2) and (c,d) can be (x1,y1)

You can take either of those.


But you CAN NOT take (a,b) as (x1,y2) or (c,d) as (x2,y1). You can not mix them.


In the question, you have to find OA and OB (B is (x,5) ) and equate them. Because both are radius of the circle. You will get x.