How do you factor #a²+4b-ab-4a#? Algebra Polynomials and Factoring Factoring by Grouping 1 Answer ProfLayton Apr 21, 2016 #=(a-4)(a-b)# Explanation: We'll solve this by factoring by grouping: #a^2+4b-ab-4a=a^2-ab-4a+4b# #=a(a-b)-4(a-b)# #=(a-4)(a-b)# Answer link Related questions What is Factoring by Grouping? How do you factor by grouping four-term polynomials and trinomials? Why does factoring polynomials by grouping work? How do you factor #2x+2y+ax+ay#? How do you factor #3x^2+8x+4# by using the grouping method? How do you factor #6x^2-9x+10x-15#? How do you group and factor #4jk-8j^2+5k-10j#? What are the factors of #2m^3+3m^2+4m+6#? How do you factor quadratics by using the grouping method? How do you factor #x^4-2x^3+5x-10#? See all questions in Factoring by Grouping Impact of this question 4061 views around the world You can reuse this answer Creative Commons License