maths 問題,,

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

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

(s + 1)/3 + (s - 1)/7 = -6
s/3 + 1/3 + s/7 - 1/7 = -6
s(1/3 + 1/7) = -6 + 1/7 - 1/3
s(10/21) = -130/21
s = -13

如果要找未知數.......
8(y-0.3)=1+2(0.3y+2)
8y-2.4=1+(0.6y+4)
8y-0.6y+4=1+2.4
7.4y+4=3.4
7.4y=3.4-4
7.4y/7.4=-0.6/7.4
y =3/37

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


(s+1)/3 + (s-1)/7 = -6
7s+7/21+3s-3/21=-6
7s+7+3s-3/21=-6
10s+4=-6
10s=-6-4
10s/10=-10/10
s=-1

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

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

3/
(s +1) / 3 + (s -1) / 7 = -6
{ 7(s +1) + 3(s -1) } / 21 = -6
{ 7s +7 + 3s -3 } = -6(21)
{ 10s +4 } = -126
10s = -130
s = -13

第一題

8y-2.4=3+0.6y
7.4y=5.4
y=1.037...
y=1.04

8(y-0.3)=1+2(o.3y+2)
8y-2.4=1+0.6+4
8y-2.4=5.6
8y=8
y=1