1)0,8x=4=4 24x-7=2x+3 3)5x-(3x+4)=7 4)2x-1=9(x-4)

1) х = (4+4) / 0.8 = 8/0.8 = 10

2) 24х - 7 - 2х - 3 = 0
22х - 10 = 0
22х = 10
х = 10/22 = 5/11

3) 5х - 3х - 4 - 7 = 0
2х - 11 = 0
х = 11/2

4) 2х - 1 - 9х+ 36 = 0
-7х + 35 = 0
35 - 7х = 7(5 - х) = 0
х = 5