Add:ab – 4a, 4b – ab, 4a – 4bAdd:ab – 4a, 4b – ab, 4a – 4b

Dear Student

When term have the same algebraic factors, they are like terms. Then, we have to add the like terms
= ab–4a + (4b–ab) + (4a–4b)
= ab–4a + 4b–ab + 4a–4b
= ab–ab–4a + 4a + 4b–4b
= ab (1 -1) + a (4 - 4) + b (4 - 4)
= ab (0) + a (0) + b (0)
= 0

Thanks