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3a+2(a-6)=-2

3a+2a-12=-2

5a=-2+12

5a=10

a=2

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-2a-2(a-4)=0

-2a-2a-8=0

-4a=0+8

-4a=8

a=2

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3(2a+5)-4a=-1

6a+15-4a=-1

6a-4a=-1-15

2a=-16

a=-8

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-5(2a-3)+3a+1=0

-10a-15+3a+1=0

-10a+3a=0+15-1

-7a=14

a=2

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4(2a+1)=3(a-2)

8a+4=3a-6

8a-3a=-6-4

5a=-10

a=-2

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0.4a-0.2(a-6)=0.5

0.4a-0.2a-0.12=0.5

0.2a=0.5+0.12

0.2a= 0.62

a=3.1

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1.3a+2a-12=-2
5a=10
a=2
2.-2a-2a+8=0
-4a=-8
a=2
3.6a+15-4a=-1
2a=-16
a=-8
4.-10a+15+3a+1=0
-7a+16=0
a=16/7
5.8a+4=3a-6
5a=-10
a=-2
6.0.4a-0.2a+1.2=0.5
0.2a=-0.7
a=-3.5

1.3a+2a-12=-2
5a-12=-2
5a=10
a=2