we need to find value of x and it is given to us that $$sqrt{1+frac{x}{961}} = frac{32}{31}$$ $$frac{32}{31}$$ = $$sqrt{frac{1024}{961}}$$ hence , $$sqrt{1+frac{x}{961}}$$ = $$sqrt{frac{1024}{961}}$$ = $$sqrt{1 + frac{63}{961}}$$
hence x = 63