Average rate of change is another name for slope
(big hint given in the units feet per second).
Slope is change in y / change in x — the slope formula is (y2 – y1)/(x2 – x1)
Use the two points (3, 6.26) and (9, 3.41) for (x1, y1) and (x2,y2).
Show your work. Because 3.41 is less than 6.26, your answer should be negative.
For this question, use the TI-84 to find the x values that make y=0. Use the table and then check your answers on the graph. Show and explain all your work.
I. Doubling is definitely exponential
II. 1 inch every 4 days is a linear function
III. 5% every 3 years is a percent change and is therefore exponential
Since this question does not ask us to solve, we can look at the structure of the equations.
We need to first notice that the second equation in all the answer choices is identical to the one given.
Therefore, all of our energy should be directed at the top(first) equation so we will compare the top equations in all 4 answers.
The correct answer will be a multiple of the top given equation:
Answer (1): -2x – 2y = -6 almost looks like -2(x – y =3)
Answer (2): -2x + 2y = 3 (if you multiply -2(x – y =3), the right hand side will have to be -6
Answer (3): 2x – 2y = 6 (this looks a LOT like x – y = 3!!!)
Answer (4): 3x + 3y = 9 almost looks like 3(x – y = 3) but not quite
There is correlation but not causation. So (1) and (2) cannot be correct.
Pay close attention to the wording — that’s it — 2 points on the Regents 🙂
