Zad 8
a) 2x + 5 + x - 2 = 12
3x = 12 - 5 + 2
3x = 9 / :3
x = 3
b) -3x - 1 + 5x + 7 = 0
2x = -7 + 1
2x = -6 /:2
x = -3
c) 4x + 7 - x + 2 = 9
3x = 9 - 7 - 2
3x = 0 /:3
x = 0
Zad 9
a) 6x + 4 = 2x /-2x
4x + 4 = 0 / -4
4x = -4 /:4
x = -1
c) -2x + 7 = 6x - 9 / -6x
-8x + 7 = -9 / -7
-8x = -16 /: (-8)
x = 2
d) -2x = 7x + 18 /-7x
9x = 18 /:9
x = 2
e) -4x + 5 = 25 - 9x / +9x
5x + 5 = 25 /-5
5x = 20 / :5
x = 4
