-4(3-b)-6=5(2a+1)+5
2(3b-4)+7=7(1-a)-10
-12+4b-6=10a+5+5
6b-8+7=7-7a-10
4b-18=10a+10
6b-1=-7a-3
10a-4b=-28
7a+6b=-2
5a-2b=-14 /.3
7a+6b=-2
15a-6b=-42
7a+6b=-2 /+
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22a=-44 /:22
a=-2
2b=5a+14,2b=5.(-2)+14=-10+14=4, b=4:2=2,b=2
/a,b/=/-2,2/
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