我按步骤解答吧
(1) 12÷X+1.8=13.8
12+1.8X=13.8X
12X=12
X=1
(2) 2(3X-1)+5=15
6X-2+5=15
6X=12
X=2
(3) 6(X-1)÷(2X-4)=3.75
6(X-1)=3.75(2X-4)
6X-6=7.5X-15
6X-7.5X=6-15
-1.5X= -9
X=6
(4) 8(X+2)-4(X-1)=60
2(X+2)-(X-1)=15
2X+4-X+1=15
X=10
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