a) 207-10x+7=84
10x=130
x=13
b)=> 3x-15=0
3x=15
x=5
c) 53+132-x=184
132-x=131
x=1
d) 85-5x=25
5x=60
x=12
e) x-4=12
x=16
a/ 1260: [207-(10x-7)]=15
207-(10x-7) =1260:15= 84
10x-7= 207-84=123
10x=123+7=130
x= 130:10=13
b/1236.(3x-15)=0
3x-15= 0:1236=0
3x =0+15=15
x =15:3=5
c/[53+(132-x)]:23=8
53+(132-x) =8.23=184
132-x =184-53=131
x =132-131=1
d/ 125-5(17-x)=100
17-x= 100:(125-5)=5/6
17-5/6=97/6
e/ x-24:6=12
x-4=12
x=12+4=16