This question could be called Linear vs Exponential as it asks for linear with fancy wording: “equal difference over an equal interval”(as opposed to just the word linear)
(I) 3.5 cm a day would make the y values go up 3.5 each day this is linear
(II) depreciate 15% a year is exponential
(III) tripling is exponential
see #25 on this Regents for long answer of linear or exponential!!
Look at the graph above the minimum y value is -7 at the point (-3,-7).
We are looking for the y = that goes even lower!!
Above is answer choice (1). You can see the minimum y value is -2 (not less than -7)
Above is answer choice (2). You can see the minimum y value is -6 (not less than -7)
Above is answer choice (3). Whoa this one goes low!! Lower than the y value of the given graph way up above
Above is answer choice (4). This graph does not go very low — it doesn’t even pass through the x-axis as its minimum y value is 2.
WODB? Which One Doesn’t Belong? see the italicized word not
study the top and bottom equations in each answer choice and compare to the original
(1) top equation exactly same as given
bottom is equivalent to the given…just all the signs are changed
(2) top equation exactly same as given
bottom all terms are doubled
(3) top all terms are tripled
bottom is the second line of answer (1) tripled or the original second line multiplied by -3
(4) is the odd one out
top is doubled
bottom: the left side is x 4 but the right side has not changed
This is a transformation both horizontal and vertical translation or moving!
The – 2 moves down the entire graph by 2 as it is faithful and does what we think it will do
Only answers (1) and (3) have been moved down
But the (x + 1) part is the horizontal shift and does the opposite of what it looks like so it will shift left
The easiest way to do this is to pick a point on the original graph like (2,3)
Move it one unit left and two units down to (1,1)
Which of the two graphs for answers (1) and (3) go through (1,1)?
From the Jan 2016 Common Core Algebra I Regents:
The level of challenge on the Regents like any exam varies quite a bit.
After posting about #1-19 of the Jan 2016 Common Core Algebra I Regents, challenge level is being added to each problem.
Please comment if you feel a problem is misclassified as I am only right about 80% of the time. Most importantly, students need to know what they find easy medium hard (often abbreviated as EMH)
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click on the word easy for blog posts for Jan 2016 1 3 4 5 8 9 12 15 16
click on the word medium for blog posts for Jan 2016 2 7 13 14 17 18 19
click on the word hard for blog posts for Jan 2016 6 10 11 20
Math Confidence by Robin the Math Lady 