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# Adding polynomials (old)

## Video transcript

add and they give us 5x squared plus 8x minus 3 plus 2x squared minus 7x plus 13x so we can really view this as just adding two polynomials and actually the second polynomial here can be simplified right off of the bat we have two like terms here we it's not the 2x squared there's no other 2x squared term in this polynomial but you have a negative 7x term and then you have a plus 13x so we could actually add these two terms what is negative 7 of something plus 13 of that something or another way to view it what's 13 X minus 7 X 13 of something minus 7 of that something well that's just going to be 6 of that something so that is just going to be 6 X and then you have your 2x squared and you have your 2x squared right over here you write it so 2x squared so this polynomial right over here simplifies to 2x squared plus 6x and we want to add it to this polynomial right over here and what we can do is what I like to do is just rewrite this polynomial under this polynomial and I'm going to align those similar terms so the turn the like terms the terms that have the same variable raised to the same power so we have X raised to the second power X raised to the second power so let's put the 5x squared over here we have an X raised to the first power we have an X raised to the first power so let's put the 8x over here and then we don't have a constant term in the first in this yellow polynomial we don't have anything raised to the 0 power any constant terms we do here so let's just put a minus 3 and then we could add these two things up we have 2x squared plus 5x squared that is 7 or something plus 5 I'm sorry 2 of something plus 5 of something is 7 of that something so it's going to be 7 X Squared's and then to that if I 6 of something and I add 8 of that something to it well I'm gonna have 14 of that something if I have 6 X's and I give you 8 more X's you're gonna have 14 X's and then we have nothing here and so if we just add nothing to negative 3 you're just going to get you're just going to get a negative 3 so this simplifies to or when we added these two polynomials we get 7x squared plus 14x minus 3