-8x+10y+12x-8y=
-9a-3x+2a+8x-3c=
9x+3c+71z+4x=
40a+58b
6a+6a=
-2b
40a+58b =
4x
4x+2y
-7a+5x+2a-3c
10x
a+7a+3x+2c+x+c=
2x+8x=
12a
18b-20b=
7a-6a=
a
3x+x =
13x+3c+71z
8a+4x+3c
