(2)0.3A=45
A=13.5 -----> A=45/0.3=150
(3)5A+4=0
5A=4 -----> 5A= -4
A=0.8 A= -0.8
(5)-3A+0.5A=10
-2.5A=10
A=4 -------> A= -4
(6)6A-4=4A-5
6A-4A=-5+4
2A=-1
A=0.5 ---------> A= -0.5
(10)4A+3(2A-3)=12-(A+4) 12后面确认是减号?
4A+6A-9=12A+48
4A+6A-12A=48+9
--2A=57
A=-28.5
(11)5A+(2-4A)=0
5A+2-4A=0
5A-4+2=0 ------>5A-4A+2=0
1A=2 -->1A=-2
A=2 -->A=-2
(12)25B-(B-5)=29
25B-B-5=29 --------> 25B-B+5=29
24B=29-5
24B=24
B=1
(14)8Y-3(3Y+2)=6
8Y-9Y+6=6 ----------->8Y-9Y-6=6
17Y=6-6 ----->-Y=6+6
Y=17 ----->Y=-12
(15)2(A+8)=3(A-1)
2A+16=3A-3
2A-3A=-3-16
-1A=13 ------>-1A=-16
A=-13 ------>A=16
(16)8A=-2(A+4)
8A-2A=8 --------->8A+2A=-8
6A=8 --------->10A=-8
A=1.33 ------>A=-0.8
(17)2(10-0.5Y)=-(1.5Y+2)
20-1Y=-1.5Y-2
-1Y+1.5Y=20-2 ---------->-1Y+1.5Y=-20-2
0.5Y=18 ---------->0.5Y=-22
Y=36 ------------>Y = -44
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