Question

find the sum and express it in simplest form. (ab+4a-6)+(ab+6)

Answer 1

= 2ab + 4a + 6 - 6

= 2ab + 4a

you can factor this  to 2a(b + 2)

Answer 2

Rewrite    (ab+4a-6)+(ab+6)    vertically:

  ab+4a-6)
+ab     +6
--------------------
2ab + 4a   (answer)