i will give you brainliest and thanks and 5 star on all of my accounts on brainliest if its correct rip my points i have 9 now :(

Answer:
4(3+x) is equivalent to 12+ 4x
If you pull 4 from each number. 12 divided by four is 3 and 4x divided by four is just x. To represent that you pulled four from both values you leave the four outside the parentheses.
To ensure that these are equivalent you can multiply out 4(3+x) and you will get 12+4x.
Explanation:
Algebra