已知x平方-6xy+9y平方=0（xy不等0）求2x-y/x+y的值

Question

已知x平方-6xy+9y平方=0（xy不等0）求2x-y/x+y的值

Answer 1

x²-6xy+9y²=0 得：(x-3y)²=0
解得：x=3y
(2x-y)/(x+y)
=(6y-y)/(3y+y)
=5y/4y
=5/4