Respuesta :

ok so

(x+1)/7 = 5/(x-1)

5(x+1)/7 = 35/7(x-1)


5x+5/35 = 35/7x-7

5/35 = 35/2x - 7

7 = 35/2x-7

14x - 49 = 35

14x = 84

x = 6