Hello there.
The answer to this question is the Distributive Property.
Remember that "distributing" means to share out. In this case, we are distributing -4 into each term within the parenthesis. Let's further evaluate on that;
-4(x+ 3);
-4(x) + -4(3);
-4x - 12.
As we can see, we multiplied -4 by each term within the parenthesis (as we did not have any sign between our number and the parenthesis, which concludes we need to multiply that term).
I hope this helps! :)
