F.1數學題數則...Plase help[10分急]

1
1/3(5X-2)=1
5X-2=3
X=1
2.
2/5(14X-8)= -20
14X-8= -50
X=-3
3
2/3(4X-1)-5= -25
2/3(4X-1)= -20
4X-1=-30
X=-29/4
4
陳太所持有的股票現值
=$220 000*(1+10%)
=$242000
5
設B君有X張$50紙幣﹐則他有30-X張$20紙幣
B君的錢數
=50X+20(30-X)
=600+30X
B君的錢數>900
600+30X>900
X>10
B君最少有11張$50紙幣

1.1/3(5X-2)=1
(5X-2)=3
5X=5
X=5

2.2/5(14X-8)=-20
28X-16=-100
X=-3

3.2/3(4X-1)-5=-25
(8X-2)=-60
X=-7.25

4.220000/20000(1+10%)(20000)
=11(110/100)(20000)
=242000

5.設X係$20既數量,Y係$50既數量
第一條式:20X+50Y>900
第二條式:X+Y=30
20X+50Y>900
2X+5Y>90
代入第二條式入第一條式
X+Y=30
X=30-Y
so
2(30-Y)+5Y>90
60-2Y+5Y>90
3Y>30
Y>10
B君最少有10張$50紙幣

1.1/3(5x-2)=1
(5x-2)=3
5x=5
x=1
2.2/5(14x-8)=-20
(14x-8)=-50
14x=-42
x=-3
3.2/3(4x-1)-5=-25
2/3(4x-1)=-20
(4x-1)=-30
4x=-29
x=-29/4
4每股股價=220000/20000
= 11
11 X 110%=12.1
12.1 X 20000=242000
5.let x be the number of $50,
50x+20(30-x)>900
50x+600-20x>900
30x>300
x>100

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

2. 2/5(14X-8)= -20
(28X)/5 - 16/5 = -20
(28x)/5 = -16.8
28x = -84
x = -3

3. 2/3(4X-1)-5= -25
2/3(4X-1) = 5
(8x)/3 -2/3 = 5
(8x)/3 =10/3
x = 10

4. 220000 X (1+10%) =242000
所持有的意思應該是指全部吧？

5. 假設有x張$20的紙幣, y張$50的紙幣
x+y=30
x=30-y ----------(1)
20x+50y=900 -------(2)
把(1)放入(2)
20(30-y)+50y=900
600-20y+50y=900
30y=300
y=10

所以有10張。

1.5x-2=1*3
5x=3+2
x=5/5
x=1
2.14x-8=-20*5/2
14x=-50+8
x=-42/14
x=3
3.2/3(4X-1)= -25+5
4x-1=-20*3/2
4x=-29
x=29/4
4.220000*(1+10%)=$242000
5.(900-20*20)/50=10