Решили уравнения:
1) (720+e)*501=365730
2) 5t+30-2t=42
3) 36*(x-3)=10-2*(x+2)

1) (720+e)*501=365730
(720+e)=365730:501
(720+e)=730
e=730-720
e=10
2) 5t+30-2t=42
5t-2t+30=42
3t+30=42
3t=42-30
3t=12
t=12:3
t=4
3) 36х - 108 = 10 - 2х - 4
36х + 2х = 10 - 4 + 108
38х = 114
х = 114/38
х = 3

(720+е)*501=365730
720+е=365730:501
720+е=730
е=730-720
е=10
5т+30-2т=42
5т-2т=42-30
3т=12
т=12:3
т=4
36(х-3)=10-2(х+2)
36х-108=10-2х-4
36х+2х=10-4+108
38х=114
х=114:38
х=3