9x-2×0.55=12.4
解：移项 9x=12.4+1.1
合并 9x=13.5
系数化为1 9x=1.5
希望采纳，谢谢。
解：解方程, 此方程的解为x = 3/2，【即x = 1.5】
9x - 2 × 0.55 = 12.4
9x - 2 × 55/100 = （12×10+4）/10
9x - 2 × 11/20 = 124/10
9x - 11/10 = 62/5
9x = 62/5 + 11/10
9x = 124/10 + 11/10
9x = 135/10
9x = 27/2
x = 27/2 ÷ 9
x = 27/2 × 1/9
x = 3/2
∴x = 1.5
答：此方程的解为x = 3/2，【即x = 1.5】
9x-2×0.55=12.4
9x=12.4+1.1
x＝1.5
9x=12.4+1.1
9x=13.5
x=1.5
9x等于12.4+1.1=13.5
x=1.5
