x+20=42+20
x=42+20
x=62
x=62-20
x=42
42+20=42+20
х+20=42+20
х+20=62
х=62-20
х=42
35+х=87-48
35+х=39
х=39-35
х=4
(15-9)×2
43-(20+7)
18:(9-7)
5*(6-3)
(19-13)+8
(19+1):4
x+20=42+20
x=42+20
x=62
x=62-20
x=42
42+20=42+20
х+20=42+20
х+20=62
х=62-20
х=42
35+х=87-48
35+х=39
х=39-35
х=4
(15-9)×2
43-(20+7)
18:(9-7)
5*(6-3)
(19-13)+8
(19+1):4