-x+(5-x)=1
and
13-(-2x+)+8
and
3x-7(x-1)=-3(2x+3)

-x+(5-x)=1
is equal to
-x+5-x=1
is equal to
5-2x=1
now add 2x to the left and right and you get
5=1+2x
now subtract 1 from left and right
2x=4
now divide by 2
x=2
-----
13-(-2x+)+8
you must say what this should be equal to...
-----
3x-7(x-1)=-3(2x+3)
is equal to
3x-7x+7=-6x-9
is equal to
-4x+7=-6x-9
now add 9 to both sides...
-4x+16=-6x
now add 4x to both sides
16=-2x
now divide by -2 and you get
x=-8

Kresho