數學中一方程2

1)請檢查有沒有打錯

2)
2y+1/5=3-y
2y+y+1/5=3-y+y
3y+1/5=3
3y+1/5-1/5=3-1/5
3y=2.8
y=14/15

3)
8x+(3x-7)/2=6
[8x+(3x-7)/2]*2=6*2
16x+3x-7=12
19x-7+7=12+7
19x=19
(19x)/19=19/19
x=1

4)
b/3-(5-b)=3
b/3-5+b=3
b/3+1b-5=3
(4/3)b-5+5=3+5
(4/3)b=8
(4/3)(3/4)b=8(3/4)
b=6

5)
x/3-x/2=1
(x/3*2/2)-(x/2*3/3)=1
2x/6-3x/6=1
(-x/6)=1
(-x/6)(-6)=1(-6)
x=(-6)

6)
3/4y=1-1/2y
3/4y+1/2y=1-1/2y+1/2y
y(3/4+1/2)=1
(5/4)y=1
(5/4)(4/5)y=1(4/5)
y=4/5

《二份之一y》=(1/2)y
《四份之三y》=(3/4)y
《三份之b》=b/3
《二份之三Ｘ減七》=(3x-7)/2
加括號就可表達~
希望幫到你~

1. x-6=x-3/4
x-x=-3/4+6
0=-3+24
0=21　　無解

2. 2y+1/5=3-y
2y+y=3-1/5
3y=3-1/5
15y=15-1
y=14/15

3. 8x+(3x-7)/2=6
16x+3x-7=12
19x=19
x=1

4. b/3-(5-b)=3
b-15+3b=9
4b=24
b=6

5. x/3-x/2=1
2x-3x=6
x=-6

6. 3/4y=1-1/2y
3y=4-2y
5y=4
y=4/5

The an is:

1.
x-6 = x-3/4
x-x = -3/4-6
so no solution

2.
2y+1/5 = 3-y
2y+y = 3-1/5
3y = 14/5
y = 14/15

3.
is it 8x+(3/2)x-7 = 6??
(8+3/2)x = 6+7
(19/2)x = 13
x = 26/19

or

8x+3x-7/2 = 6??
(8+3)x = 6+7/2
11x = 19/2
x = 22/19

4.
b/3-(5-b) = 3
b/3-5+b = 3
(4/3)b = 3+5
(4/3)b = 8
b = 6

5.
x/3-x/2 = 1
(1/3-1/2)x = 1
-1/6x = 1
x = -6

6.
3/4y = 1-1/2y
(3/4+1/2)y = 1
5/4y = 1
y = 4/5

1.
x-6 = x-3/4
x-x = -3/4-6
so no solution

2.
2y+1/5 = 3-y
2y+y = 3-1/5
3y = 14/5
y = 14/15

3.
is it 8x+(3/2)x-7 = 6??
(8+3/2)x = 6+7
(19/2)x = 13
x = 26/19

or

8x+3x-7/2 = 6??
(8+3)x = 6+7/2
11x = 19/2
x = 22/19

4.
b/3-(5-b) = 3
b/3-5+b = 3
(4/3)b = 3+5
(4/3)b = 8
b = 6

5.
x/3-x/2 = 1
(1/3-1/2)x = 1
-1/6x = 1
x = -6

6.
3/4y = 1-1/2y
(3/4+1/2)y = 1
5/4y = 1
y = 4/5