a) 2x + 7 = -(3 - x)
2x + 7 = -3 + x
2x - x = -3 - 7
x = -10
b) (2x + 1) : 8 = x : 8
2x + 1 = x
1 = x - 2x
1 = -x
x = -1
c) 2(3-x) - 4(x-5) = 2x + 2
6 - 2x - 4x + 20 = 2x + 2
-6x + 26 = 2x + 2
8x = 24
x = 3
d) 15x + 3(1 - 2x) = 9x
15x + 3 - 6x = 9x
9x + 3 = 9x
3 [tex]\neq[/tex] 0 . równanie sprzeczne.
