F.1的數學

(1.)4A-A=6
3A=6
A=2
(2.)1=5Y
Y=0.2
(3.)2A+4=3+7
2A=10-4
2A=6
A=3
(4.)15=6+2B+B
9=3B
B=3
(5.)4X-4=8X-8
8-4=8X-4X
4X=4
X=1
(6.)3X-2=X-8
3X-X=-8+2
2X=-6
x = -3
(7.)2x+1+2=x-5
2X-x=-5-3
x =-8
(8.)15-[R-6]=6R+5
15-R+6 =6R+5
-R-6R =5-21
-7R =-16
R =2.2857
(9.)2[X+1]=5+3X-1
2X+2 =5+3X-1
2X-3X =4-2
X =2
(10) 15/50 x0.1
=0.03
=3%
(11)90 x [1+30%]
=117
(12) 240/[1+50%]
=160
(13)90/60 X100%
=1.5%

答案我未必會講...多數得過程
1 4A-A=6
3A=6
A=?
2 1=5Y
Y=1/5
3 2A+4=3+7
2A+4=10
2A=14
A=?
4 15=6+2B+B
21=3B
B=?
5 4X-4=8X-8
12X=-4
X=-?
6 3X-2=X-8
2X=-6
X=?
7 2X+1+2=X-5
X=-5-1-2
X=?
8 15-[R-6]=6R+5
10=6R+R-6
R=16/7
9 2[X+1]=5+3X-1
2X+2=5+3X-1
2X-3X=5-1-2
-X=2 (X=-2)
10 15/50x100%
= ? 0%
11 90x(1+30%)
=1??
12 設某數是X:
Xx(1+50%)=240
X=240除(1+50%)
X=???
13 90-60除60x100%
=?0%

以上答案唔知係咪一定岩...

1. 4A - A=6
A=2
2. 1=5Y
Y=0.2
3. 2A+4=3+7
A=3
4. 15=6+2B+B
B=3
5. 4X-4=8X-8
X=3
6. 3X-2=X-8
X=-3
7. 2X+1+2=X-5
X=-2
8. 15-[R-6]=6R+5
R=3 5/7
9. 2[X+1]=5+3X-1
X=-2
10.15是50的百分之幾?
30%
11.若90增加30%求增加後的新數值.
117
12.某數增加50%後是240,求該數.
160
13.若60增至90,求百分增加.
50%

1) 3A=6 2)1=5Y
A=2 1
------=Y, Y =0.2
5

3)2A+4=10 4) 3B+6=15
2A=6 3B=9
A=3 B=3

5)4X+4=8X 6)3X-2=X-8
4X+4=8X 3X=X-6
4=4X 4X=-6
X=1 X=-1.5

7)2X+3=X-5 8)15-(R-6)=6R-5 9) 2(X+1)=5+3X-1
2X+8=X -R-6=6R-20 2X+2=3X+4
X=-8 5R=-20 2X-2=3X
R=4 X=-2
10) 15
---------- X100%=30%
50

11)90x(1+30%)=117
12)150%x=240
1.5x=240
x=160
13) 90-60
------------------x100%=50%
60

2008-01-02 16:15:03 補充：
Q7 的ans 為-8Q8 的ans 為4Q9 的ans 為-2

2008-01-02 16:17:48 補充：
Q8 should be 26------ 7I feel sorry that I have made some mistake

1. A=2
2. Y=0.2
3. A=3
4.B=3
5.X=1
6.X= -3
7.X= -8
8. R= 2 2/7
9.X= -2
10. 30%
11. 117
12. 160
13. 增加 50%

1. A=2
2. Y=0.2
3. A=3
4. B=3
5. X=3
6. X=-3
7. X=-2
8. R=3 5/7
9. X=-2
10. 30%
11. 117
12. 160
13. 50%

我幫你!!!要唔要步驟???

1. 2
2. 0.2
3. 3
4. 3

WAIT... 一陣比埋其他你...

2008-01-02 16:09:33 補充：
5. 16. 37. 8