If the points(x, 4) lies on a circle whose centre is at the origin and radius is 5, then x =

It is given that the point A(x, 4) is at a distance of 5 units from origin O.

So, apply the distance formula to get,

$5^{2}=(x)^{2}+4^{2}$

Therefore,

$x^{2}=9$

So,

$x=\pm 3$

So the answer is (b)