What should come in place of both x in the equation x/√128 =√162/x .

Let	x	=	√162
	√128		x

Then x² = √128 x 162

   = √64 x 2 x 18 x 9

   = √8² x 6² x 3²

   = 8 x 6 x 3

   = 144.

 x = √144 = 12.