Question

3x的平方减xy除以9x的平方减6xy加y的平方=3x除以多少?

Answer 1

答案是 9x-3y;(或者3(3x-y));
(3x^2-xy)/(9x^2-6xy+y^2)
=[x(3x-y)]/[(3x-y)^2]
=x/(3x-y)
=(3x)/[3(3x-y)];