Răspuns :
x=23-y
3.(23-y)+7y=113
69-3y+7y=113
4y=113-69
4y=44
y=44:4=11
x=23-11 =12
V :3x12+7x11=36+77=113
3.(23-y)+7y=113
69-3y+7y=113
4y=113-69
4y=44
y=44:4=11
x=23-11 =12
V :3x12+7x11=36+77=113