Odpowiedź:
a)
x+ 5 =-4
x = -4 - 5 = -9
d)
x:5=20 /*5
x = 20 * 5 = 100
8)
-2x = 14 /:(-2)
x = -7
j)
30 - 3x = 21
-3x = 21 - 30 /:(-3)
x = 9/3 = 3
m)
7x - 6= -20
7x = -20 + 6 /:7
x = -14/7 = -2
b)
x - 7 = 15
x = 15 + 7 = 22
e)
2x = 40 /:2
x = 20
h)
2x + 1 = 13
2x = 13 - 1 /:2
x = 12/2 = 6
k)
14 – 2x=-4
-2x = -4 - 14 /:(-2)
x = 18/2 = 9
n)
17 + 2,5x = 32
2,5x = 32 - 17 /:2,5
x = 15/2,5 = 6
c)
7 - x = 15
-x = 15 - 7 /*(-1)
x = -8
f)
0,3x = 9 /:0,3
x = 30
i)
4x - 2 = 14
1)
3 - 5x = 43
-5x = 43 - 3 /:(-5)
x = -40/5 = -8
o )
5x + 1 = 3
5x = 3 - 1 /:5
x = 2/5
Szczegółowe wyjaśnienie: