方程數學的問題(thx)

1. 11-7y+3=-7
11-7y+3-3=-7-3
11-7y=-10
11-11-7y=11-(-10)
7y=11+10
7y=21
7y除7=21除7
y=3

2. 5h+1-4h=10
(5+1.4)h=10
6.4h=10
6.4h除6.4=10除6.4
h=1又9/16




3. 6m-11m+2=22
6m-11m+2-2=22-2
6m-11m=20
(6-11)m=20
-5m=20
-5m除-5=20除-5
m=-4



4. 19-7b-5b=-53
19-(7+5)b=-53
19-12b=-53
19-19-12b=19-(-53)
12b=19+53
12b=72
12b除12=72除12
b=6

(1) 11-7y+3=-7
11+3+7=7y
21=7y
y=3

(2) 5h+1-4h=10
5h-4h=10-1
h=9

(3) 6m-11m+2=22
2-22=11m-6m
-20=5m
m=-4

(4) 19-7b-5b=-53
19+53=5b+7b
72=12b
b=6