Question

数学初一题目计算 和方程①y+1/2=2-y/3（注：就是：y加二分之一等于三分之2-y）②x-3/2-4x+1/5=1

Answer 1

①y+1/2=(2-y)/3

y+1/2=2/3-y/3

(1+1/3)y=2/3-1/2

4y/3=1/6

y=1/8

②(x-3)/2-(4x+1)/5=1

x/2-3/2-4x/5-1/5=1

(1/2-4/5)x=1+3/2+1/5

-3x/10=27/10

x=-9

③(y+2)/2-(2y-1)/8=1

4(y+2)-(2y-1)=8

4y+8-2y+1=8

2y=-1

y=-1/2

④2(x-3)-3(2x+1)=6(1-x)

2x-6-6x-3=6-6x

(2-6+6)x=6+6+3

2x=15

x=15/2=7.5

⑤5(x+8)-5=6(2x-7)

5x+40-5=12x-42

(5-12)x=-42-40+5

-7x=-77

x=11