[tex]\text{First term,}~ a = x+1\\\\\text{Common ratio,}~ r = \dfrac{x-3}{x+1}= \dfrac{x-1}{x-3}\\\\\text{Now,}\\\\~~~~~~\dfrac{x-3}{x+1} = \dfrac{x-1}{x-3}\\\\\\\implies (x-3)(x-3) = (x-1)(x+1)\\\\\\\implies (x-3)^2 = x^2 -1\\\\\\\implies x^2 -2\cdot 3x +3^2 =x^2 -1\\\\\\\implies -6x+9=-1\\\\\\\implies -6x = -1 -9\\\\\\\implies -6x = -10\\\\\\\implies x =\dfrac{-10}{-6}\\ \\\\\implies x = \dfrac 53[/tex]