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CCSS.Math:

Leigha and pedro pushed two tables together the figure below shows the new arrangement so we have table number one and table number two the lia and pedro have pushed together maybe they're having a bunch of people over for a fancy breakfast and so they've pushed one two tables together to have a lot of room for people to sit and we're asked what is the perimeter of the new figure perimeter is the distance around the outside so all of this space around the outside is the perimeter and we need to figure that out so what we could do we could say here we know there's three meters around the outside here's another meter so that's four meters around the outside but then we get to here and uh we don't have this one and we don't have this side length or this length or this link so we can't know the entire distance around the outside until we figure out what those missing side links are so let's fill in some of those first because these tables are rectangles opposite sides are equal so if this side down here is one meter then this side up here has to be one meter same here if this is three meters the opposite side is also three meters and we have one meter on the end of this a table so the inside this length from here to here is also one meter but that's an interesting one this one meter here because this part now right here that's on the inside of the arrangement that's not the outside so that is not part of the perimeter so this one meter will not be included in our perimeter but it is still important to us and here's why this length and this length are part of the outside and we need to know how long those are so what we can say is if this entire length is three meters then this entire length is three meters but one of those meters was moved to the inside so how many meters are still left here on the outside we had three meters over here we moved one to the inside so we have two meters left on the outside so this length and this length are a total of two meters we can't know for sure they look pretty evenly divided we can't know for sure that they're both one meter but we do know for sure that it's a total of two meters when we can bind them so again this one meter is not on the outside it's not part of our perimeter but it did help us to find the other links okay now everything is labeled so we can get back to finding the perimeter the distance around the outside will be all of these lengths put together so here we have one meter plus moving down the outside three more meters plus one more plus one here on that side we just figure it out plus another three one on the end another long side of three and finally one more meter going up the side so we can add these links when we combine these links they'll tell us the total distance around the outside one plus three is four plus one more is five plus one more is 6 6 plus 3 is 9 9 plus 1 is 10 10 plus 3 is 13 and 13 plus one more is 14 so the perimeter of the new figure of this new table arrangement is 14 meters