Here is the applicable portion from the web site I posted earlier:
Distributive Property
The distributive property is actually a very simply concept to learn and apply. It will allow you to simplify something like 3(6x + 4), where you have a number being multiplied by a set of parenthesis. Let’s start with a simple problem:
6(4 + 2)
Based on the order of operations, you know that anything inside parenthesis should be done first. Adding 4 + 2 is simple enough, resulting in this:
6(6)
When you see a number next to parenthesis like this, it means multiplication, so what we really have here is this (remember that * means multiplication):
6 * 6 = 36
If you can’t figure this out, you are hopelessly confused.
If 6(6)=36 then 2(12) must equal 24.
What happens when you take 48/2 and “distribute” it to (9 + 3)?
You get 24 times 9 plus 24 times 3.
Which is 216 + 72
Which is 288.
Using the distributive property.
48/2(9+3)
Don’t distribute first! Distribution is a multiplication operation, which is done *after* the operations in parenthesis. When the ops in parens are evaluated first, there is no distribution left to do:
48/2(9+3) = 48/2(12) = 48/2*12 = 24 * 12 = 288
Parens first
Mult and div next
Add and subt last
If 2 operators have equal precedence, evaluate from left to right.