若x^2-y^2=24,x+y=6,求(x-y)^2的值.
问题描述:
若x^2-y^2=24,x+y=6,求(x-y)^2的值.
快
半小时之内
答
x²-y²=24
(x+y)(x-y)=24
6(x-y)=24
(x-y)=4
(x-y)²=16