Category Archives: Regents

Get the Math and the Points Aug 2018 CC Algebra I Regents #7

August 2018 CC Alg I 7
4x^2 – 25 is the difference of two squares as 4x^2 is a perfect square as (2x)^2 and 25 is a perfect square as 5^2.
You can find the answer by:
FOILing each of the four choices
or
Putting 4x^2 – 25 into Y1 and putting each of the others into Y2 and then either graphing to see they are the same or checking the table to see they are the same
or
Can pick a number for x like 10 and putting 10 in for x into the original expression and then into each of the choices

Get the Math and the Points! CC Alg I Regents Aug 2018 #3

August 2018 CC Alg I 3

This question can be done with or without the TI-84.
Notice in answer (1) that -8 x -8 will give +64 which does not match the trinomial
Notice in answer (2) that FOIL’s Outer and Inner +8m – 8m which will cancel out the middle term and does not match -12m
In (3) and (4), we are looking for the middle terms that add up to -12m we just have to watch our signs!
That’s it — that’s two points!
To check work with a TI-83/4, put m^2 – 12m -64 into Y1 and then try each of the others into Y2.
Check the graph and the tables…when you find the match, that is David’s correct factoring!