#2

The eqn of circle will be sumthing like

(x-h)² + y² = 5² = 25   since the y coordinate of centre will be zero

now this circle passes thru pt (2,3)

so put x= 2 and y = 3 in this eqn

the eqn becomes :

4 + h² - 4h + 9 = 25

h² - 4h  -12 = 0

h² - 6h + 2h -12 = 0

=> h = 6 or -2

Put these values of h in the original eqn, u will get the requisite answer

Rate if this helps u

Cheers!!