Question

Плиз...3х+12*(х-2)=66, 8а-45=5а+30, 5*(х-42)=3х-110

Answer 1

1) 3х+12х=66-24
15х=42
х=2.8

2) 8а-5а=45
3а=45
а=15

3) 5х-210=3х-110
2х=100
х= 50

Answer 2

8а-45=5а+30
8а-5а=30+45
3а=75
А=25
_____________
8*25-45=5*25+30
155=155