1) (5020+X):25=360
5020+Х = 360*25
5020+Х = 9000
Х = 9000 - 5020
Х = 3980;
2) 820:X*4-16=32
820:X*4 = 32 +16
820:X*4 = 48
820:X = 48 : 4
820:X = 12
Х = 820 :12
Х = 68
3) 1000-X:36=388
X:36 = 1000 - 388
X:36 = 612
Х = 612 * 36
Х = 22032
4) (5080-X:5)*3=13935
5080-X:5 = 13935 : 3
5080-X:5 = 4645
Х : 5 = 5080 - 4645
Х : 5 = 435
Х = 435*5
Х = 2175
периметр = 4*25
периметр = 100