762.
3(х-7)+5х=3х - 21+5х=8х - 21
3(4-3х)+8х=12-9х+8х=12-х
(у-4)*2+10у=2у-8+10у=12у-8
(2у+5)*4-11у=8у+20-11у=20-3у
4х+2*(0,5х+3)=4х+х+6=5х+6
6х-3*(х-7)=6х-3х+21=3х+21
751.
1. ..........= - 5
1) -2 1/3 + 3 7/12= - 2 4/12+3 7/12=1 3/12=1 1/4
2) 1,5+1 1/4=1,5+1,25=2,75
3) 6,5 - 2,75=3,75
4) - 1,25 - 3,75= - 5
2. ..............= - 3 1/6
1) - 2 1/6 + 5 1/4= - 2 2/12+5 3/12=3 1/12
2) 1,75+3 1/12=1 3/4+3 1/12==1 9/12+3 1/12=4 10/12=4 5/6
3) 5,6 - 4 5/6=5 3/5 - 4 5/6=5 18/30 - 4 25/30=23/30
4) - 2,4 - 23/30= - 2 2/5 - 23/30= - 2 12/30 - 23/30= - 3 5/30= - 3 1/6
??
1,8 - ( 2 3/5 -(х-1,2))=3
1,8 - 2,6+х - 1,2=3
- 2+х=3
х=5
1,9-(5 3/4 -(х+1))=3,15
1,9 - 5,75+х-1=3,15
- 4,85+х=3,15
х=3,15+4,85
х=8