若﹛2010X+2011y=2009,2011X+2010y=2012.求（x+y)²+（x-y)²的值.
问题描述：
若﹛2010X+2011y=2009,2011X+2010y=2012.求（x+y)²+（x-y)²的值.
答
2010x+2011y=2009 (1)
2011x+2010y=2012 (2)
(1)+(2)
4021x+4021y=4021
x+y=1
(2)-(1)
x-y=3
(x+y)²+(x-y)²=1²+3²=1+9=10