Question

cum se rezolva ecuatiile de la exercitiul 2

Answer 1

a)(13·x-416:4):7=13
13·x-104=13·7
13·x-104=91
13·x=91+104
13·x=195
x=195:13
x=15

b)(123·x-1278):149=36
123·x-1278=36·149
123·x-1278=5364
123·x=5364+1278
123·x=6642
x=6642:123
x=54

c)6-5:[4-3:(2-2:x)]=1
5:[4-3:(2-2:x)]=6-1
5:[4-3:(2-2:x)]=5
4-3:(2-2:x)=5:5
4-3:(2-2:x)=1
3:(2-2:x)=4-1
3:(2-2:x)=3
2-2:x=3:3
2-2:x=1
2:x=2-1
2:x=1
x=2:1
x=2

d) 420:(160-1000:x)+24·7=180
420:(160-1000:x)+168=180
420:(160-1000:x)=180-168
420:(160-1000:x)=12
160-1000:x=420:12
160-1000:x=35
1000:x=160-35
1000:x=125
x=1000:125
x=8

e) 1+{2·[3+(x-4)·5]:6}·7=8
2·[3+(x-4)·5]:6·7=8-1
2·[3+(x-4)·5]:6·7=7
2·[3+(x-4)·5]:6=7:7
2·[3+(x-4)·5]:6=1
2·[3+(x-4)·5]=1x6
2·[3+(x-4)·5]=6
3+(x-4)·5=6:2
3+(x-4)·5=3
(x-4)·5=3-3
(x-4)·5=0
x-4=0:5
x-4=0
x=4

f) [(x+2²):2³-3²:3]·2⁴=2⁵-?
[(x+4):8-9:3]·16=32-?