几道一元一次方程计算题

1：3x-1/2[2x-(5x-1)-4]=0

2：Y/5-Y-1/2=1-Y+2/5

3:X/0.7-.017-0.2X/0.03=1

要有过程 写得好有的加分

1.6x-2x+5x-1+4=0 x=-3

2.2y-10y-5=10-10y+2 2y=17 y=17/2

3. x/7-2x/3=11.7 3x-14x=35.1 x=-35.1/11

1.3x-x+1/2(5x-1)+2=0

2x+5/2 x-1/2+2=0

9/2 x=-3/2

x=-1/3

2.Y/5-1/2=1+2/5

Y/5=3/2+2/5=19/10

Y=19/2

3.10x/7-0.17-20x/3=1

30x/21-140x/21=1.17

-110x/21=117/100

-110x=117*21/100

x=-117*21/11000=-2457/11000

1： 3x-1/2[2x-(5x-1)-4]=0 2：Y/5-Y-1/2=1-Y+2/5

3x-1/2(-3x-3)=0 2Y-10Y-5=10-10Y+2

6x+3x+3=0 2Y=17

9x=-3 Y=8.5

x=-1/3

第3题第二个数是0.17还是想表示0.017呢

3x - 1/2[2x - 5x+1-4]=0 3x- 1/2[-3x-3]=0 3x+(3x+3)/2=0 6x+3x+3=0 9x+3=0 9x= -3 x= -1/3

y移到左边，-1/2移到右边 6y/5 -y =3/2+2/5 y/5=15/10+4/10 两边同乘以5 y= 15/2+4/2=7.5+2=9.5

3X-1/2[2x-(5x-1)-4]=6X-2X+(5X-1)+4=4X+5X-1+4=9X+3=0 X=-1/3

Y/5-Y-1/2=1-Y+2/5 →2Y-10Y-5=10-10Y+4 →2Y-5=14 → 2Y=19 Y=19/2

X/0.7-.017-0.2X/0.03=1 →0.03X-0.021-0.14X=0.021→ -0.11X=0.04 →X=-4/11