1) 4000 - х * 8 = 160
х * 8 = 4000 - 160
8х = 3840
х = 3840 : 8
х = 480
--------------------------------
2) 4000 - х * 2 = 160
х * 2 = 4000 - 160
2х = 3840
х = 3840 : 2
х = 1920
--------------------------------
3) 4000 - 4 * х = 160
4 * х = 4000 - 160
4х = 3840
х = 3840 : 4
х = 960
--------------------------------
4) у - 400 * 3 = 800
у - 1200 = 800
у = 800 + 1200
у = 2000
--------------------------------
5) у - 400 * 4 = 800
у - 1600 = 800
у = 800 + 1600
у = 2400
--------------------------------
6) 400 * 3 - у = 800
1200 - у = 800
у = 1200 - 800
у = 400
--------------------------------
7) d : 4 = 4228 : 7
d : 4 = 604
d = 604 * 4
d = 2416
-------------------------------
8) d : 8 = 4228 : 7
d : 8 = 604
d = 604 * 8
d = 4832
9) d : 4 = 2114 : 7
d : 4 = 302
d = 302 * 4
d = 1208
----------------------------
Наибольшие корни уравнений в 5), 7) и 8).