Skip to main content

Graphing

Submitted by an LD OnLine user on

Oh hate me…

After the great responses I got on factoring and foil from Sue and Victoria (printed them out, applied them, lived them, loved them, learned them:)
I am at it again…
Well there is this thing called graphing, eh? You have yourself a slope, a x intercept, a y intercept, functions, and quadratic equations and all of that…tables of values….and so on and so forth…
Oh gosh no, I am not asking for a good twenty percent of Algebra II to be virtually taught to me from this web site..oh no. I am just in a quandary, see.
My quandary is that I really have tried to comprehend these topics. Like I swear to Jesus Christ , I have tried. I prepared for the lecture on these topics over the weekend with a total of three Algebra II level books that explain things in painstaking detail. Today, I sat in the front row of the class and took notes (to really piss poor effect and I really figured I could have at least been able to copy the notes off the board) and tried to comprehend the exact same topics my professor lectured upon that I studied up on all weekend. They are chapter 19 and 20 of my book, so they were not hard to cross reference.
I cannot comprehend this at all. Just not at all. I have a very powerful calculator that I could very well use on my test and final but I do not want to not ever learn this. I have a TI89 I use at home becasue it has a symbolic math guide that, after a good three tries of doing it alone, I will use to show me how to set up an equation(and pelase remember that I have really bad dyscalculia, like grade six level math skills they told me)
. For tests of any sort, I use a TI83 because I am no cheater…but I am coming close to using my more powerful calulator if I do not figure this out and just really do not want to and yet I do not want to straight up fail…so I just do not know what to do basically.

Does any educator out there know of any, well I do not want to say easy, but just simple way to do at least some of this graphing?

The text my University uses is called Basic Math, Algebra„ Geometry, and Applications by Cheryl Cleaves and it sucks because it shows you examples for the most simple method of doing anything and then you can use those examples with explinations for the first five (sometimes seven) homework problems and then as they get harder, think like from number seven to eighty, you have no example to go by…in the preface of the book they call this the spiral approach to math and I am figuring that some of you folks might know what that is. I just know it means hell because it basically means (FOR EXAMPLE) you have a good point of reference when you do your homework for an equation like 5+X=7 and there might be five or seven problems like that…but then you get an equation like 5/7X+3=? nd you just haven’t any frame of reference at all, honest to goodness truth. What is really swell and has driven me to drastically increase my coffee consumption for the hours it takes me to try and comprehend some of this…is that the instructors of the developmental studies maths at my university all just go by the book!
Have any of you folks heard of this spiral learning approach? And anything about this graphing?

Submitted by victoria on Tue, 08/03/2004 - 4:15 AM

Permalink

merlin — I want to give you the complete answer and it is no trouble at all, but tonight the new tenant wants to get his computer online too so I have to sign off quickly. Get back to me in a day or two, really no problem.

The spiral approach has both good and bad points. I’ll talk to you about it later. Teaching by copying examples from the book is not good; is anyone trying to teach you concepts?

Graphing is a GOOD thing. Graphing is a way to visualize relationships. All the stuff about slopes and y-intercepts is details; don’t lose the forest for the trees.
You have two letters, most commonly x and y. Other letters can be used, exactly the same thing, look at the concept and don’t get hung up on the letters. You ask the question “When I change x, what happens to y?” or “When I change the number I put in, what happens to the output?”

Example: the price to mail a lpackage in a certain country is $1.50 plus ten cents per ounce. How much to mail a tiny package less than an ounce? A one-ounce package? A two-ounce package? … A one-pound (16-ounce) package? Two pounds?
x, youtr input, is the weight. Y, your output, is the price.
You get a table of values:
X Y
0

Submitted by victoria on Tue, 08/03/2004 - 4:20 AM

Permalink

This got cut off earlier; here’s the finished first part.

merlin — I want to give you the complete answer and it is no trouble at all, but tonight the new tenant wants to get his computer online too so I have to sign off quickly. Get back to me in a day or two, really no problem.

The spiral approach has both good and bad points. I’ll talk to you about it later. Teaching by copying examples from the book is not good; is anyone trying to teach you concepts?

Graphing is a GOOD thing. Graphing is a way to visualize relationships. All the stuff about slopes and y-intercepts is details; don’t lose the forest for the trees.
You have two letters, most commonly x and y. Other letters can be used, exactly the same thing, look at the concept and don’t get hung up on the letters. You ask the question “When I change x, what happens to y?” or “When I change the number I put in, what happens to the output?”

Example: the price to mail a lpackage in a certain country is $1.50 plus ten cents per ounce. How much to mail a tiny package less than an ounce? A one-ounce package? A two-ounce package? … A one-pound (16-ounce) package? Two pounds?
x, your input, is the weight. Y, your output, is the price.
You get a table of values:
X (weight) Y (cost)
0 1.50
1 1.60
2 1.70
… … …
16 3.10
32 4.70

OK, now let’s draw a picture of how this works. Your book has instructions how to set up a graph, just follow them.

Your graph shows a straight line starting at $1.50, the minimum price, and sloping steadily upwards. If you run your finger along it, you follow the price rising as the weight rises. That’s all it’s about, just a picture of how things relate.

There are several more examples but I have to check the rest of the board and get off line fast, so more to come later.

Back to Top