ab−mn+an−bm=?(a) (a−b)(m−n)(b) (a−m)(b+n)(c) (a−n)(m+b)(d) (m−a)(n−b)
ab−mn+an−bm=ab+an−bm−mn=a(b+n)−m(b+n)=(b+n)(a−m)
Question 20
For non-zero numbers a and b, (ab)m÷(ab)n, where m>n, is equal to: (a)(ab)mn (b)(ab)m+n (c)(ab)m−n (d)((ab)m)n