Odpowiedź:
a)
13 x + 5 = 31
13x = 31 - 5 /:13
x = 26/13 = 2
b)
-8x + 5 = - 7
-8x = -7 - 5 /:(-8)
x = 12/8 = 3/2 = 1 1/2
c)
7x - 5 = 6x + 8
7x - 6x = 8 + 5
x = 13
d)
3 - x = 2x + 1
-x - 2x = 1 - 3
-3x = -2 /:(-3)
x = 2/3
e)
9x + 3 = 7(x - 2) + 17
9x + 3 = 7x - 14 + 17
9x - 7x = 3 - 3
2x = 0
x = 0
f)
- ( x - 2) + 3(x - 1) + 2 = 0
-x + 2 + 3x - 3 + 2 = 0
2x + 1 = 0
2x = -1 /:2
x = -1/2
Szczegółowe wyjaśnienie: