a) 101×[101-(101-102:X)] = 202
101-(101-102:X) = 202:101
101-(101-102:X) = 2
101-102:X = 101-2
101-102:X = 99
102:X = 101-99
102:X = 2
X = 102:2
X = 51
Verificare:
101×(101-99) = 101×2 = 202
b) 369-[(x+112):5+113]=434
(X+112):5+113 = 369-434
(X+112):5+113 = -65
(X+112):5 = -(65+113)
(X+112):5 = -178
X+112 = -178×5
X+112 = -890
X = -(890+112)
X = - 1 002
Verificare:
369-(-890:5+113) = 369-(-65) = 369+65 = 434