Pre alg. I'm feeling pretty dumb about now.

1. Oct 2, 2006

bewilderee

first off the question I'm stuck on is..

2(3.2) + 2(6.4)=

Factor by using the distributive law of real numbers in reverse.

For the life of my this is just not clicking. It's either too late or I'm incapable. ugh!
I went back and read the part on reverse distributive properties, it says, " The reverse of the distributive property is called factoring. The following are some examples."

4(3) + 4(2)= 4(3+2) - the real number factor, 4 is called the common factor of the addends.

I'm thinking I probably need to drag out my book from my last math class and look up factoring. This should be on the homework help page..but they didn't have a section for lowly pre algebra

2. Oct 2, 2006

HallsofIvy

The distributive law says a(b+ c)= ab+ ac. In other words, adding b and c first and then multiplying by a is the same as first multiply each by a and then adding. In your 4(3) + 4(2)= 4(3+2), 4 plays the part of "a" above. Since there is a "4" in each part of the sum, it can be "taken out" as a factor.

Now go back to "2(3.2) + 2(6.4)= ". Do you see that 2 multiplying each of 3.2 and 6.4? That's ab+ ac with a= 2, b= 3.2 and c= 6.4. And it is equal to a(b+ c). What is that in terms of your numbers?

3. Oct 2, 2006

bewilderee

thanks

I've got it now. How they got four was throwing me. It just didn't click that they were factors as they sat.. I kept looking for common factors among the factors, haha... go fig'r