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7x÷7=28÷7 X=4 (136) x-56=1 X=56+1 X=57 (137) 8-7x=1 8-7x+7x=1+7x 7x+1-1=8-1 7x=7 X=1
(138) x-30=12 X-30+30=12+30 X=42 (139) 6x-21=21 6x-21+21=21+21 6x=42 6x÷6=42÷6 X=7 (140) 6x-3=6 6x-3+3=6+3 6x=9 6x÷6=9÷6 X=1.5 (141) 9x=18 9x÷9=18÷9 X=2 (142) 4x-18=14 4x-18+18=14+18 4x=32 4x÷4=32÷4 X=8 (143) 5x+9=11 5x+9-9=11-9 5x=2 5x÷5=2÷5 X=0.4 (144) 17-2x=11 17-2x+2x=11+2x 2x+11-11=17-11 2x=6 2x÷2=6÷2 X=3 (145) x+4+8=23 X+12=23
X=23-12 X=11 (146) 7x-12=9 7x-12+12=9+12 7x=21 7x÷7=21÷7 X=3 (147) X-5.7=2.15 x=5.7+2.15 X=7.85 (148) 5X-2X=18 3x=18 3x÷3=18÷3 X=6 (149) 3X +0.5=5 3x+0.5-0.5=5-0.5 3x=4.5 3x÷3=4.5÷3 X=1.5 (150) 3.5×2= 4 x 4x=7 4x÷4=7÷4 X=1.75 (151) 26×1.5= 2x 2x=39 2x÷2=39÷2 X=18
(152) 0.5×16―16×0.1=4x 4x=6.4 4x÷4=6.4÷4 X=1.6 (153) 9.26-X=0.402 X=9.26-0.402 X=8.858 (154) 36.9÷X=0.3 X=36.9÷0.3 X=123 (155) X÷0.5=2.6 X=0.5×2.6 X=1.3 (156) 93-5x=80 93-5X+5X=80+5X 5X+80-80=93-80 5X=13 5X÷5=13÷5
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X=2.6 (157) 180-6x=54 X=6
180-6X+6X=54+6X 6X+54-54=180-54 6X=126 6X÷6=126÷6 X=21 (158) 9+4x=40 4X+9-9=40-9 4X=31 4X÷4=31÷4 X=7.75
(159) 0.2x-0.4+0.5=3.7 0.2X-0.5+0.5-0.4+0.4=3.7-0.5+0.4 0.2X=3.6 0.2X÷0.2=3.6÷0.2 X=18 (160) 9.4x-0.4x=16.2 9X=16.2 9X÷9=16.2÷9 X=1.8 (161) 92-4x=20 92-4X+4X=20+4X 4X+20-20=92-20 4X=72 4X÷4=72÷4 (162) X=18 (163) 7x÷6=1.4 7x÷6×6=1.4×6 7X=8.4 7X÷7=8.4÷7 X=1.2 (163) 16x+34x=1 50X=1 50X÷50=1÷50 X=0.02 (164) 18x-14x=12 4X=12 4X÷4=12÷4 X=3 (165) 3 x-42÷14=15 3X-3=15 3X-3+3=15+3 3X=18 3X÷3=18÷3
(166) 12+4x=56 4X+12-12=56-12 4X=44 4X÷4=44÷4 X=11
(167) 22-14x=12 22-14X+14X=12+14X 14X+12-12=54-12 14X=42
14X÷14=42÷14 X=3
(168) X+8.3=10.7
X=10.7-8.3 X=2.4
(169) 5x =30
5X÷5=30÷5 X=6
(170) x-5.6=9.4
X=5.6+9.4 X=15
(171) x÷0.8=90
X=0.8×90 X=72
(172) 3x-8=16
3X-8+8=16+8 3X=24 3X÷3=24÷3 X=8
(173) 3x+9=27
3X+9-9=27-9 3X=18 3X÷3=18÷3 X=6
(174) 5.3+7x=7.4 7X+5.3-5.3=7.4-5.3
7X=2.1 7X÷7=2.1÷7 X=0.3 (175) 3x÷5=4.8 3X=4.8×5 3X=24 3X÷3=24÷3 X=8
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(176) X-0.8X=6
0.2X=6
0.2X÷0.2=6÷0.2
X=30
(177) 12x+8x=4.8
20X=4.8 20X÷20=4.8÷20 X=24
(178) 7(x-2)=49
7X-14=49 7X-14+14=49+14
7X=63 7X÷7=63÷7 X=9
(179) 4×8+2x=36 2X+32=36 2X+32-32=36-32 2X=4 2X÷2=4÷2
X=2
(180) (x-2)÷3=7
X-2=3×7
X-2=21 X=23
(181) x÷5+9=21 X÷5=21-9 X÷5=12 X=12×5 X=60
(182) (300-x)÷5=30 300-X=30×5
300-X=150 X=300-150 X=150
(183) 91÷x =1.3 X=91÷1.3 X=70
(184) 41-3x=17 41-3X+3X=17+3X 3X+17-17=41-17 3X=24 3X÷3=24÷3 X=8