已知x²-3xy=5,xy+y²=3,求x²-2xy+y²的值

问题描述:

已知x²-3xy=5,xy+y²=3,求x²-2xy+y²的值

x²-3xy=5,xy+y²=3,
x²-2xy+y²=x²-3xy+xy+y²=5+3 = 8