Question

rezolvati in multimea Z ecuatia 3*(x+7)=12; 5*(3-2x)=-10; 32:(-2x)=1; -2*(x+9)=-28; 2x:|-5|=8; 7*(2-x)=|-42|

* = inmultirea

Answer 1

Răspuns:

Explicație pas cu pas:

3*(x+7)=12;

3x+21=12

3x=12-21

3x=-9

x=-9/3

x=-3∈Z

5*(3-2x)=-10;

15-10x=-10

-10x=-10-15

-10x=-25

x=-25/(-10)

x=25/10- simplificăm cu 5    =>   x=5/2∉Z

32:(-2x)=1;

-2x=32

x=32/(-2)

x=-16∈Z

-2*(x+9)=-28;

-2x-18=-28

-2x=-28+18

-2x=-10

x=-10/(-5)

x=2∈Z

2x:|-5|=8;

2x=8x5

2x=40

x=40/2

x=20∈Z

7*(2-x)=|-42|

14-7x=42

-7x=42-14

-7x=28

x=28/(-7)

x=-4∈Z