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use the commutative law of addition let me underline that the commutative law of addition to write the expression five plus eight plus five in a different way and then find the sum now this commutative law of addition sounds like a very fancy thing but all it means is if you're just adding a bunch of numbers it doesn't matter what order you do not add the numbers in so we could add it as five plus eight plus five we could order it as five plus five plus eight we could order it eight plus five plus five these are all going to add up to the same things and it makes sense if I have five of something and then I add eight more then I add five more I'm going to get the same thing as if I had took five of something then added the five then added the eight and you could try all of these out you'll get the same thing now they say in a different way and then find the sum the easiest one to find the sum of actually let's do it all of them but the easiest one just because a lot of people immediately know that five plus five is ten is to maybe start with the five plus five so if you have five plus five that's ten plus eight is equal to 18 now let's verify that these two are the same exact thing up here five plus eight is 13 13 plus five is also 18 that is also 18 if we go down here 8 plus 5 is 13 13 plus five is also equal to 18 so no matter how you do it no matter what order you do it in and that's the commutative law of addition sounds very fancy but just means that order doesn't matter if you're adding a bunch of things