Odpowiedź :
a) x + 7 = -2
x = -2 - 7
x = -9
b) -9 + x = 12
x = 12 + 9
x = 21
c) x - 4 = 6
x = 6 + 4
x = 10
d) x - 21 = -42
x = -42 + 21
x = -21
e) 5 + x = 3
x = 3 - 5
x = -2
f) x + 46 = 87
x = 87 - 46
x = 41
a) x+7=-2
x=-2-7
x=-9
b) -9+x=12
x=12+9
x=21
c) x- 4=6
x=6+4
x=10
d) x-21=-42
x=-42+21
x=-21
e) 5+x=3
x=3-5
x=-2
f) x+46=87
x=87-46
x=41