Question

11. Rezolvaţi în mulțimea Z ecuația: a) 3. (x + 7) = 12; c) 5.(3-2x) = -10; e) 32:(-2x) = 1; b) -2-(x +9) = -28; d) 2x:1-5) = 8; f) 7.(2-x)=1-421.​

Answer 1

a) x+7 = 12: 3

x+7 = 4

x = 4-7

x = -3

b) x+9 = -28:(-2)

x+9 = 14

x= 14-9

x =5

c) 3-2x = -10:5

3-2x = -2

-2x = -2-3

-2x = -5

x = 5/2

d) 2x :5 = 8

2x = 8*5

2x = 40

x = 40:2

x = 20

e) -2x = 32: 1

-2x = 32

x = 32:(-2)

x = -16

f) 7(2-x) = 42

2-x = 42:7

2-x = 6

-x = 6-2

x = -4