Get the Math and Points Jan 2016 CC Alg I #10

From the January 2016 Common Core Algebra I RegentsJan 2016 Alg I 10

Read this question carefully:  How much is 2 subtracted from 10?  10-2
Apply that to the problem above and we need to do:
5x^2 – (2x – 3)^2
We will need to FOIL (or double distribute) the (2x – 3)^2
(2x – 3) (2x – 3)
F:  (2x)(2x) = 4x^2
O: (-3)(2x) = -6x
I:  (-3)(2x) = -6x
L:  (-3)(-3) = 9
combine the like terms of -6x and -6x for -12x
4x^2 -12x +9  and subtract it from 5x^2 so it really looks like this:
5x^2 – (4x^2 – 12x +9) and the negative is distributed in the next line
5x^2 – 4x^2 + 12x – 9 then combine like terms and you have
x^2 + 12x – 9
match this up carefully — the answers look super similar

We could also use the TI-84 with Y1 for the original and Y2 for the answer choices
see below for answer choice (1)  this is NOT a match as the tables list different y values for the same x values and there are clearly 2 different graphs (red and blue)

Let’s try answer choice (2)  see below  also NOT matching up as the tables list different y values for the same x values and there are clearly 2 different graphs (red and blue)

ok onto answer choice (3) and look at the table for same values in Y1 and Y2!!!
Jan 2016 Alg I 10cJan 2016 Alg I 10c tableJan 2016 Alg I 10c graph

Unfortunately the TI-84 graph does not show the overlap of Y1 and Y2 in answer choice 3 but at least we do not see e can see that there are not 2 different functions being graphed

 

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