Step-by-step explanation:Find the common factor of 6 and 18, which is 6. So you would put 6 outside of the parenthesis and the other factors multiplied by it inside the parenthesis(x and 3). If this is confusing then then in other words the common multiple of 6x and 18 is 6 so 6 divided by 6x is x so x goes in the parenthesis and 18 divided by 6 is 3 so 3 also goes in the parenthesis.that is what 6(x+3) stands for. I also simplified 15(x+3)by solving it to see it meant 15x+45 and the GFC(greatest common factor) is 15 and 15x divided by 15 is x and 45 divided by 15 is 3, so the GCF(15) goes outside the parenthesis and you put x and 3 inside the parenthesis.Which explains to you the 15(x+3). Hope this helps!
