Răspuns :

x   = -4 + 1 = - 3
x = 2 +6 = 8
x =5+4=9
x = 14-7 =7

x-1=-4=> x =-4+1 => x = -3 ; x-6=2 => x =2+6 => x= 8; 5=-4+x => x = 5+4 => x=9 ; 7+x=14 => x = 14-7 => x = 7