數學題(中一）方程式聽日交help!!!!!

1.
1.3x - 7 = 2.5x - 1
-6 = 1.2x
x = -5

2.
4n - 11 - 8n = 22 - n
-4n - 11 = 22 - n
-33 = 3n
n = -11

3.
8(y - 0.3) = 1 + 2(0.3y + 2)
8y - 2.4 = 1 + 0.6y + 4
7.4y = 1 + 4 + 2.4
7.4y = 7.4
y = 1

4.
h-[2(h-1) + 10] = 5(h-34)
h-[2h - 2 + 10] = 5h - 170
h - 2h + 2 - 10 = 5h - 170
-h - 8 = 5h - 170
-6h = -162
h = 27

2007-10-17 19:03:04 補充：
你的「1.3y-7=2.5x-1」應是「1.3x-7=2.5x-1」之誤。

1) 1.3x-7=2.5x-1
1.3x-2.5x=-1+7
-1.2x=6
x=-5

2)4n-11-8n=22-n
4n-8n+n=22+11
-3n=33
n=-11

3)8(y-0.3)=1+2(0.3y+2)
8y-2.4=1+0.6y+4
8y-0.6y=1+4+2.4
7.4y=7.4
y=1

4)h-(2(h-1)+10)=5(h-34)
h-(2h-2+10)=5h-170
h-2h+2-10=5h-170
-h-8=5h-170
-h-5h=-170+8
-6h=-162
h=27

1. 1.3y-7=2.5x-1
1.3y-2.5x=-1+7
1.3y-2.5x=6

2. 4n-11-8n=22-n
-4n-11=22-n
-4n+n=22+11
-3n=33
n=-11

3. 8(y-0.3)=1+2(0.3y+2)
8y-2.4=1+0.6y+4
8y-0.6y=5+2.4
7.4y=7.4
y=1

4. h-(2(h-1)+10)=5(h-34)
h-(2h-2+10)=5h-170
h-2h+2-10=5h-170
-h-8=5h-170
-h-5h=-170+8
-6h=-162
h=27