38+x=80. x-38=42. 80-x=38
х=42, 80-38. х=80,38+42. х=42 , 80-38
80-х=38 х=80-38 х=42 80-42=38 38+х=80 х=80-38 х=42 38+42=80 х-38=42 х=42+38 х=80 80-38=42
38+х=80. х-38=42. 80-х=38 х=80-38. х=38+42. х=80-38 х=42. х=80 х=42