中一題目 請解答

3.
3 = 0.5x + x
3 = 1.5x
x = 2
4.
-2y - 13 = 3y + 2
-13 - 2 = 3y + 2y
-15 = 5y
y = -3
5.
7 + 8f = 5f + 34
8f - 5f = 34 - 7
3f = 27
f = 9
6.
4(h + 3) - 2 + h = 8h + 2
4h + 12 - 2 + h = 8h + 2
5h + 10 = 8h + 2
10 - 2 = 8h - 5h
8 = 3h
h = 8/3 or 2 2/3
9.
5[2(x + 1) + x] = 11x - 2
5(2x + 2 + x) = 11x - 2
5(3x + 2) = 11x - 2
15x + 10 = 11x - 2
15x - 11x = -2 - 10
4x = -12
x = -3

3) 1.5x=3
x=2

4) 5y=-15
y=-3

5) 3f=34-7
3f=27
f=9

6) 5h+10=8h+2
3h=8
h=8/3

9) 10(x+1)+5x=11x-2
10x+10+5x=11x-2
4x+10=-2
4x=-12
x=-3

3) 3=0.5x+x
1.5x=3
x=2

4) -2y-13=3y+2
-13-2=3y+2y
-15=5y
-3=y
y=-3

5) 7+8f=5f+34
8f-5f=34-7
3f=27
f=9

6) 4(h+3)-2+h=8h+2
4h+12-2+h=8h+2
4h+h-8h=2-12+2
-3h=-8
h=8/3

9) 5[2(x+1)+x]=11x-2
5(2x+2+x)=11x-2
10x+10+5x=11x-2
10x+5x-11x=-2+10
4x=8
x=2

3)3=0.5x+x
3=1.5x
x=2

4) -2y-13=3y+2
-5y=15
y=-3

5) 7+8f=5f+34
3f=27
f=9

6) 4(h+3)-2+h=8h+2
5h+10=8h+2
8=3h
h=8/3

9) 5[2(x+1)+x]=11x-2
5(3x+2)=11x-2
15x+10=11x-2
4x=-12
x= -3

3. 3 = 0.5x + x

3 = 0.5x + x
3 = 1.5x
x = 2

4. -2y - 13 = 3y + 2

-2y - 13 = 3y + 2
-13 - 2 = 3y + 2y
-15 = 5y
y = -3

5. 7 + 8f = 5f + 34

7 + 8f = 5f + 34
8f - 5f = 34 - 7
3f = 27
f = 9

6. 4(h+3) - 2 + h=8h + 2

4(h + 3) - 2 + h = 8h + 2
4h + 12 - 2 + h = 8h + 2
5h + 10 = 8h + 2
10 - 2 = 8h - 5h
8 = 3h
h = 8/3 or 2 2/3

9. 5[2(x + 1) + x] = 11x - 2

5[2(x + 1) + x] = 11x - 2
5(2x + 2 + x) = 11x - 2
5(3x + 2) = 11x - 2
15x + 10 = 11x - 2
15x - 11x = -2 - 10
4x = -12
x = -3

3)3=3/2x
6=3x
x=2
4)-15=5y
y=-3
5)3f=27
f=9
6)5h+10=8h+2
h=4
9)5[2(x+1)+x]=11x-2
x=-3

2006-11-28 21:48:52 補充：
6)4h 12-2 h=8h 25h 8=8h3h=8h=2 2/3

3) 3 = 0.5x+x
3 = 1.5x
3/1.5 = x
2 = x
x = 2

4) -2y-13=3y+2
-13 - 2 = 3y+2y
-15 = 5y
-15/5 = y
-3 = y
y = -3

5) 7+8f=5f+34
8f - 5f = 34 - 7
3f = 27
f = 27/3
f = 9

6) 4(h+3)-2+h = 8h+2
4h+12 - 2+h = 8h+2
5h+10 = 8h+2
10 - 2 = 8h - 5h
8 = 3h
h = 8/3

9) 5[2(x+1)+x]=11x-2
5(2x+2+x) =11x-2
5(3x+2) =11x - 2
15x+10 = 11x - 2
15x - 11x = -2-10
4x = -12
x = -12/4
x = -3

3)3=0.5x+x
3=1.5x
x=2

4) -2y-13=3y+2
-2y-3y=2+13
-5y=15
y= -3

5) 7+8f=5f+34
8f-5f=34-7
3f = 27
f=9

6) 4(h+3)-2+h=8h+2
4h+12-2+h= 8h+2
12-2-2=8h-4h-h
8=3h
h=8/3
h=2.667


9) 5[2(x+1)+x]=11x-2
5(2x+2+x)=11x-2
10x+10+5x=11x-2
10x+5x-11x= -2-10
4x= -12
x=-3

3) 3=0.5x+x

3=1.5x
3/1.5=x
x=2

4) -2y-13=3y+2

-2y-3y=+2+13
-5y=15
y=-3

5) 7+8f=5f+34

8f-5f=34-7
3f=27
f=9

6) 4(h+3)-2+h=8h+2

4h+12-2+h=8h+2
5h+12=8h+4
12-4=8h-5h
8=3h
h=8/3

9) 5[2(x+1)+x]=11x-2

5(2x+2+x)=11x-2
15x+10=11x-2
4x=-12
x=-3

3)
3=0.5x+x
3=1.5x
x=2

4)
-2y-13=3y+2
-5y=15
y=-3

5)
7+8f=5f+34
3f=27
f=9

6)
4(h+3)-2+h=8h+2
5h+10=8h+2
8=3h
h=8/3

9)
5[2(x+1)+x]=11x-2
5(3x+2)=11x-2
15x+10=11x-2
4x=-12
x= -3