Word problem

Let father's age be x yrs and son's age be y yrs

Now his age is square of his son age x = y^{2   ................}.(i)

The age of father and son one year ago will be x-1 and y-1

So x-1 =8y-8

so x = 8y - 7   .........(ii)

from (i) and (ii) 

y² = 8y - 7 

So y = 7,1

y=1 does not satisfy the condition so  y =7 yrs is son's age

and x = 49 yrs is father's age