Question

最后一题，因式分解

因式分解 x2-y2+4x+6y-5，谢谢。

Answer 1

=x2+4x+4-y2+6y-9=(x+2)2-(y-3)2=(x-y+5)(x+y-1)

Answer 2

x2-y2+4x+6y-5
=(x2+4x+4)-(y2+6y+9)
=(x+2)2-(y-3)2
=(x+2+y+3)(x+2-y-3)
=(x+y+5)(x-y-1)