计算:+=_________.
25x2+_______+y2=(5x+y)2.
若x=2﹣,则x2﹣4x+8=_______.
当a=b+时,a2﹣2ab+b2=_______.
(x﹣y)2+_______=(x+y)2.
若x2﹣mx+16=(x﹣4)2,那么m=_______.