约分:a²+4ab-5b²/ax-by+ay-bx
问题描述：
约分:a²+4ab-5b²/ax-by+ay-bx
答
=(a+5b)(a-b)/[x(a-b)+y(a-b)]
=(a+5b)(a-b)/(x+y)(a-b)
=(a+5b)/(x+y)