Ответы и объяснения

2013-04-22T16:00:47+00:00
1)
....
24-16x-x+2=9
17-17х=0
-17х=-17
x=1
2)
....
5х-12x-42=13-х-1
5x-12х+х=-1+42+13
-7x+х=41+13
-6x=54
x=-9
2013-04-23T00:51:00+00:00

1) 8(3-2x)-(x-2)=9

24-16x-(x-2)-9=0

24-16x-x+2-9=0

24-17x+2-9=0

26-17x-9=0

17-17x=0

x=-(-17)/17

x=17/17

x=1


2) 5x-6(2x+7)=13-(x+1)

5x-(12x+42)-13+x+1=0

5x-12x-42-13+x+1=0

-7x-42-13+x+1=0

-7x-55+x+1=0

-6x-55+1=0

-6x-54=0

x=-54/6
x=-9