Răspuns :
a+b=702
a-b=b:4 => a=b+b:4 = 5b:4
5b:4+b=702
9b:4=702
9b=702x4
9b=2808
b=312
a=5x312:4 = 390
a-b=b:4 => a=b+b:4 = 5b:4
5b:4+b=702
9b:4=702
9b=702x4
9b=2808
b=312
a=5x312:4 = 390
x+y=702
x-y=y:4
x=y+y:4
5y:4
5y:4+y=702
9y:4=702
9y=702x4
9y=2808
y=312
x=5x312:4
x=390
x-y=y:4
x=y+y:4
5y:4
5y:4+y=702
9y:4=702
9y=702x4
9y=2808
y=312
x=5x312:4
x=390