Răspuns :
a+b=130
a-b=30
a=b+30
b+30+b=130
2b=100
b=50
a=50+30
a=80
a+b=2068
a-b=400
a=b+400
b+400+b=2068
2b=1668
b=834
a=834+400
a=1234
a-b=30
a=b+30
b+30+b=130
2b=100
b=50
a=50+30
a=80
a+b=2068
a-b=400
a=b+400
b+400+b=2068
2b=1668
b=834
a=834+400
a=1234
1) x+y=130
x-y=30 adunam cele 2 ecuatii si obtinem
2x / =160 =>x=80
y=130-80=50
2)x+y=2068
x-y=400 adunam cele 2 ecuatii si obtinem
2x= 2468 =>x= 1234
=>y=2068-1234 =834
x-y=30 adunam cele 2 ecuatii si obtinem
2x / =160 =>x=80
y=130-80=50
2)x+y=2068
x-y=400 adunam cele 2 ecuatii si obtinem
2x= 2468 =>x= 1234
=>y=2068-1234 =834