Răspuns :
a = b - 18
2a + b = 873
2 * (b - 18) + b = 873
2b - 36 + b = 873
3b = 909
b = 909 : 3
b = 303
a = 303 - 18
a = 285
2a + b = 873
2 * (b - 18) + b = 873
2b - 36 + b = 873
3b = 909
b = 909 : 3
b = 303
a = 303 - 18
a = 285
a=b+18
2a+b=873=>2*(b+18)+b=873=>2b+36+b=873=>3b=801
b=801:3
b=267
a=b+18
a=267+18
a=285
2a+b=873=>2*(b+18)+b=873=>2b+36+b=873=>3b=801
b=801:3
b=267
a=b+18
a=267+18
a=285