From the January 2016 Common Core Algebra I Regents:
Y=, graph, table
Looking for zeros!!!
Where do you see the parabola crossing the x-axis on the graph?
For what values of x does y have a value of zero?
Look at the answers carefully — they are trying to trick us with negative signs!!
and that’s it!! You just got 2 more points awesome!!!
PS on Parts II, II, IV you would be expected to factor this but with multiple choice
From the January 2016 Common Core Algebra I Regents
Put 1300(1.02)^7 into the TI-84, it will come out to more than 1300!!
The money is growing and also since 1.02 >1, the money is increasing.
So it has to be growth which is either answer 2 or 4
The exponential growth formula given on the Regents reference sheet is way complicated.
Here is a much much better one:
In our equation A = 1300 (1.02)^7
1300 is the principal or starting amount and the time = 7
The number in the parentheses is (1.02) which is equal to (1 + r)
Therefore r = .02 which is 2 cents or 2%
Now look at answers (2) and (4)
Notice that .02% growth would have the decimal .0002 as r and this is not the case.
1st step: distribute x(x-12) and then add 34
so you will now have y = x^2 – 12 x +34 or you could type in:
y = x(x-12) +34 without even distributing
Put either of those into Y1 and try answer (1) in Y2, like this…not a match!! The tables are different as is the graph!
Now try answer (2) below also not a match
Next, choice (3) nope not a match
Choice 4 below, the tables match and the graphs are exactly the same — therefore we can only see one parabola! You just got 2 more points :)
From the January 2016 Common Core Algebra I Regents
Key questions to ask about this literal (only letters no numbers) equation;
But first a regular looking equation of 5x = 10
How do you solve 5x = 10? (s’s will say divide by 5)
So how many x’s? (5)
see below for an example of a literal equation
We divide both sides by r because that is how many t’s there are!! r t’s
How many r’s are in Prt?
There would be Pt r’s in Prt so we would start with
I = Prt and divide both sides by Pt
so that would be I/ Pt.
2 points :)
3From the Jan 2016 Common Core Algebra I Regents
First entry point into this question:
What is the y intercept? Where does the line cross the y-axis?
The equation of a line is y = mx + b (m=slope, b = y-intercept)
That would be at (0,-3) making the equation y = mx – 3
Leaving only answers (1) and (2)
Second entry point:
Does the line have a positive or negative slope? It goes up from left to right so it has to be a positive slope leaving answers (1) and (2) still
Third entry point:
Is the shading above or below the line?
We will use the symbol on the TI-83 that looks just like our graph above as students must know how to say/think/read the inequality symbol (this knowledge/skill is not easy to assess as people have a 50/50 chance of guessing if the inequality sign is greater or less than!!)
But look below, entering y ≥ 2x – 3, voila we have a match!!!
Math Confidence by Robin the Math Lady 