<p>I think I got possibly 4 wrong maximum</p>
<p>Most likely 1 or 2 wrong which score can that be</p>
<p>i don’t think the curve will be very generous - i thought the math was very easy so there will probably be lots of high scores… -3=33 doesnt seem likely imo</p>
<p>I chose the double L graph, with the break at 1500 kwh.
I figured that since the price is the same, its cost would decrease suddenly??</p>
<p>no thats ridiculous. its simple analytically but even more simple if u think about it using calculus</p>
<p>after 1500 watts u have the percent increase = (11+.067(1500)+(.062(1500-x)) all over (7+.064?(1500)+.062(1500-X)) or in other words a rational functions where both the numerator and denominator are linear functions. Evaluate the limit as x goes to infinity and u will see that the percent increase will go to 0 since that function will =1/1. There are no jumps since the function is also continuous.</p>
<p>for the one with two equations wasnt the answer two because then 6 would equal 6 and then there would be infinite solution </p>
<p>i put 2</p>
<p>no it was 4</p>
<p>set both equations equal to each other and find the value of a.</p>
<p>The one about the perimeter of the trapezoid was found by treating one of the sides of the trapezoid like a right triangle. </p>
<p>See, there was a line which divided the trapezoid bisymetrically, straight down the center vertically. That line was the longer leg of the triangle. But there was the top side to contend with, so you got rid of it and subtracted its length from the shorter leg, and solved for c (the hypotenuse) using the Pythagorean Theorem. </p>
<p>I know everyone here knows this, but some of the people who I tested with today had issues with it, even though it was a simple problem.</p>
<p>Which reminds me: I didn’t finish the Math section. Not even close. I was short at least 9 problems. </p>
<p>I hate math, and if you like math, well I hate you too.</p>
<p>what is this L or V shaped graph that you’re all talking about >.>
i dont remember it.
I remember the kwh problem (one of the answers was 57% or sumthing) but I dont quite remember the graph…</p>
<p>@pi face- the graph problem was right after the 57% problem- you had to choose which graph represents % increase from old to new</p>
<p>@masteropponent - i will repost my explanation from the last page for the company graph problem. if you follow the steps and enter exactly what i post on your calculator, you should get the same results:
Company graph- The graph is L-shaped; proven by making the actual graph.
Steps to replicate my reasoning:
First i graphed the % increase for X≤1500
<em>the ≤ and > signs are in your calculator in Test (2nd->Math)</em>
Y1=(7+.066<em>X)/(X≤1500) --turn this graph off
Y2=(11+.067</em>X)/(X≤1500) --turn this graph off
Y3=(Y1/Y2-1)*100 --making it a percent, graph ON</p>
<p>The second piece of the graph is for % increase X>1500
Y4=(7+.066<em>1500+.062</em>(X-1500))/(X>1500) --off
Y5=(11+.067<em>1500+.062</em>(X-1500))/(X>1500) --off
Y6=(Y5/Y6-1)*100 --making it a percent, graph ON</p>
<p>This yields an L shaped graph.</p>
<p>coop—im agrreing with u not disagreeing.</p>
<p>^oh. i sorta think i remember it. basically what i did was plug in 2k, 3k, and 4k and find the graph which had those points. i think it was an L shape…</p>
<p>I got the L-shaped one. The jump discontinuity. That was one of two that I was really struggling on.
And the one with the rate was REALLY HARD idk how it was done… I put the one without the 1500 minus whatever… because that had nothing to do with the rate, right?
Plus, I had 5 minutes left and had to speed.
The i one was A.
Dude, epic fail right here. And to think - I got 800 on the math SAT… so much for that temporary moment of glory.
32, if I’m lucky… 
■■■</p>
<p>@viny- if you plug in 2 for a you get:
that the first equation’s graph will be y=-2/3x+2
and the 2nd equation’s graph will be y=-2/3x+1</p>
<p>These are parallel lines and have NO solutions.
To have infinite solutions, the graphs must be exactly the same (they must have the same y=mx+b equation). When the graphs are right on top of each other, i.e. the same, they are always equal to each other and therefore have infinite solutions.</p>
<p>ah yeah my bad master- i misread the post before yours and thought he was agreeing with me</p>
<p>Oh, and a was 4.
I took Linear Algebra (university course) so I did that “shortcut”. I was used to seeing questions like this so I was able to answer it instantly. If you look carefully, although the two entries in the second “row” of the matrix created by the system of equations was double that of the first, the augmented part (“B” in the system AX=B) of that row was actually half the first row. So in order for there to be infinitely many solutions and NOT an inconsistency, you would have to perform a row operation such that the entire second row are ALL zeros. This is only possible if the second row is a multiple of the first (i.e. the corresponding vectors are collinear) so in order for this to happen, you would have to multiply by 4. Therefore a is 4. </p>
<p>Sorry if this makes no sense, but I’m 100% sure of my answer.</p>
<p>@futurephysician- are you saying the L graph was the jump discontinuity? because it was actually the L without the jump</p>
<p>I am pretty sure the correct graph was the L shaped graph.</p>
<p>the correct answer did not have a jump</p>
<p>I believe it was choice A?</p>
<p>it is- if you look earlier in the thread i explain how to actually graph it (it is the L without a jump discontinuity)</p>
<p>huh?</p>
<p>the correct answer did not have a jump discontinuity. Are u saying it does?</p>