saludos anavic....

x - 1 = y + 1

x + 1 = 2(y - 1)

x = y + 2 ==> y + 2 + 1 = 2y - 2 ==> 5 = 2y - y ==> y = 5, x = 7

burro ==> 5
mulo ==> 7

Coke.