7*х+21=100-16, х: 121-1265=3647, 787*х=7286=20 259, 120+х*3=375, 24000: (х-12) = 80, х: 26+1654=2610

7x+21=100-16

7x=84-21

7x=63

x=63:7

x=9

x:121-1265=3647

x:121=3647+1265

x:121=4912

x=4912*121

x=594 352

787x-7286=20 259

787x=20 259 + 7286

787x=27 545

x = 27 545 : 787

x = 35

120+x3=375

x3=375-120

x3=255

x=255:3

x=85

24000: (x-12) = 80

Х-12 = 24000:80

Х-12=300

Х = 300+12

Х=312

x:26+1654=2610

x:26=2610-1654

x:26=956

x=956*26

x=24856