幫幫我 ,, 數學 ,,,,急急急急!!!

1 ) 9k – 1 = - 6k – 31
9k + 6k = 1 – 31
15k = - 30
∴ k = - 2


2 ) 10 - 5x = 1 – x + 1 + 2x
10 - 5x = 2 + x
10 – 2 = x + 5x
6x = 8
x = 8/6
∴ x = 4/3


3 ) 0.4a - 0.2 (a - 6) = 0.5
0.4a - 0.2 a + 1.2 = 0.5
0.2 a + 1.2 = 0.5
0.2 a = 0.5 – 1.2
0.2 a = - 0.7
a = (- 0.7) / 0.2
∴ a = - (7/2)


4 ) 5[2(y - 4.2) + y - 1] = y - 5
5[2y – 8.4 + y - 1] = y - 5
5(3y – 9.4) = y - 5
15y – 47 = y – 5
15y – y = 47 – 5
14y = 42
∴ y = 3


5 ) 19 - 7b - 5b = - 53
19 - 12b = - 53
19 + 53 = 12b
12b = 72
∴ b = 6


6 ) 2(2x - 1) = 6
4x - 2 = 6
4x = 6 + 2
4x = 8
∴ x = 2


7 ) 3(2 - z) = - 9
6 - 3z = - 9
6 + 9 = 3z
3z = 15
∴ z = 5


8 ) 16 = - 8 (5p + 8)
16 = - 40p – 64
64 + 16 = - 40p
80 = - 40p
- 40p = 80
∴ p = - 2


9 ) 5(7 + 3q) + 12 = 2
35 + 15q + 12 = 2
15q + 47 = 2
15q = 2 – 47
15q = – 45
∴ q = - 3



希望幫到您！

1) 9k-1=6k-31
3k=-30
k=-10

2) 10-5x=1-x+1+2x
-6x=-8
x=4/3

3) 0.4a-0.2(a-6)=0.5
0.4a-0.2a+1.2=0.5
0.2a=-0.7
a=-3.5

4) 5[2(y-4.2)+y-1]=y-5
5(2y-8.4+y-1]=y-5
5(3y-9.4)=y-5
15y-47=y-5
14y=42
y=3

5) 19-7b-5b=-53
-12b=-72
b=6

6) 2(2x-1)=6
4x-2=6
4x=8
x=2

7) 3(2-z)=-9
6-3z=-9
-3z=-15
z=5

8) 16=-8(5p+8)
16=-40p-64
80=-40p
p=-2

9) 5(7+3q)+12=2
35+15q+12=2
15p=-45
p=-3