Ответы и объяснения

2013-02-10T03:28:27+04:00
2013-02-10T03:31:44+04:00

1. 3х+6/11=0;
3х=-6/11;
х=-2/11. 

 

2. 20-14х=12-4(2х-5);

20-14х=12-8х+20;
6х=-12;
х=-2.

 

3. (7-х)/6=(19х-11)/8;
(4(7-х)-3(19х-11))/24=0;
(28-4х-57х+33)/24=0;
-61х+61=0;
х=1.

 

4. 17-2(х+3)+5(х-7)-3(2х+1)=-28;
17-2х-6+5х-35-6х-3=-28;

3х=17-6-35-3+28;

3х=1;
х=1/3.

 

5. (2х-3)/5+(х-1)/4+(5х+1)/20=3-х;
8х-12+5х-5+5х+1=60-20х;
18х-16=60-20х;
38х=76;
х=2.