x²-12xy+36y²=0,则x-5y/x+5yA. 1/11 B. 1/y C. 11 D. y/11
问题描述：
x²-12xy+36y²=0,则x-5y/x+5y
A. 1/11 B. 1/y C. 11 D. y/11
答
x=6y
6y-5y/6y+5y=1/11
A
答
x²-12xy+36y²=0
(x-6y)²=0
x=6y
(x-5y)/(x+5y)
=(6y-5y)/(6y+5y)
=1/11
所以选 A