Question

ab – mn + an – bm =? 

A. (a-b)(m-n) 

B. (a-m)(b+n) 

C. (a-n)(m+b) 

D. (m-a)(n-b)

Answer 1

= ab – mn + an – bm = ab + an – mn – bm 

= a(b + n) – m(n + b) 

= (a – m)(b + n).