(广州)计算下面各题,能简便的尽量简便. (1)(+﹣)÷ (2)[﹣(﹣)]× (3)20.07×1994﹣19.93×2007 (4)2.5×0.875+0.25×1.25 (5)999+99+9+ (6)2.5﹣﹣÷.
80÷x=2012x+8x-12=28 (2x-1)+10=371.6x+3.4x-x-5=27 (3x+5)÷2=(5x-9)÷3x-21×=4x÷=÷
3x+7x+10=903(x-12)+23=35 7x-8=2x+275x-18=3–2x
x+4=10 x-12=348x=96 4x-30=08.3x-2x=63x÷10=5.2
(x- 4.5)=7x-25%x=10
3x=5(32-x)0.36×5-x=