x²-xy+4y-4y=(x²-xy)+4x-4y)=x(x-y)+4(x-y)=(X-y)(X+4)仿照上述分解因式的方法qingnifenjiead-ac-bc+bd

问题描述:

x²-xy+4y-4y=(x²-xy)+4x-4y)=x(x-y)+4(x-y)=(X-y)(X+4)仿照上述分解因式的方法qingnifenjiead-ac-bc+bd

ad-ac-bc+bd
=(ad-ac)+(bd-bc)
=a(d-c)+b(d-c)
=(a+b)(d-c)