This can be easily solved by checking the answers: we will need a + and – to create a – so answers (1) and (2) are gone.
Look at (4): If we multiply (24.5x)(24.5x) we definitely get more than 49x^2 so finding this answer is easy.
Students can also put 49x^2 – 36 into Y1 on the TI-84 and then try each of the answers into Y2 and see which creates the same graph and/or table.
That’s it, 2 more points on the Regents!!
Using the TI-84 makes this an easy question — we can see that the two functions — a linear and an absolute value intersect once at (2,4)…then we have to read clearly to see if the question is asking for x or y. Get the Math and get 2 more points!!
Look at the difference between the Given and Step 1…
A great visual to compare the above to is:
https://profteacher.com/2009/12/11/distributive-property/
https://www.khanacademy.org/math/algebra-basics/alg-basics-algebraic-expressions/alg-basics-distributive-property/e/distributive-property-with-variables
That’s it — two points!
Definition of a function:
Every x maps to a unique y
Notice Jan has 31 days and that’s it
March has 31 days and April has 30 days
But the number of days in February depends on leap year vs non leap year
So which month maps to two outputs?
(https://www.timeanddate.com/calendar/months/
Using substitution, we can rewrite the second equation as
3(-2x + 2x + 8) = 12
3(8) = 12
24 = 12
huh? NO solution
If we were to solve the second equation for Y=, we would get:
by distributing the 3
-6x + 3y = 12
add 6x to each side
3y = 6x + 12
Divide both sides by 3
y = 2x + 4 this is parallel to the first line y = 2x + 8 and therefore the lines will never meet
making the answer “No solution”
Math Confidence by Robin the Math Lady 