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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!

October 2018 Brain Puzzler Solution

Q: A Math quiz has $3$ multiple-choice questions, each with $3$ choices. A student passes the quiz with $2$ or more correct questions. If the student randomly picks their answers, what is the probability of passing the quiz?

A: 7/27  = 1/27 + 6/27
Scenario 1: The student gets all 3 correct (1/3) x (1/3) x (1/3) = 1/27
Scenario 2: The student gets 2 correct.  1/3 x 1/3 x 2/3 but this can happen 3 different ways as the student could get the 1st one incorrect or the 2nd or the 3rd.
so (1/3)x (1/3) x (2/3) x 3 = 6/27
1/27 + 6/27 = 7/27.