my teacher explains stuff on the board in text format, and i barely understand it. my dad does it a little bit better, but i still don't understand it.

i find that the best way i learn is in a visual format, if i can create a picture in my head, I'll remember it for ever.
like, in science i can picture and understand atoms perfectly, but when we went to molecules, lipids, proteins and stuff like that, it just fucked me over.

from what my dad explained to me, i understand that the variable B will affect the place the line will intersect with the Y axis.

my dad cant explain to me what Y, M or X is equal to, from what he tells me, i cant even comprehend it.


please help me!


right now, i just know how to graph it by what was implanted into me by hours of repeating the same thing, i know how to do it, but i dont understand. and i know that once i run into it, but a little bit different i will have no idea what to do.

i know now that:

y=mx+b

so if y=4+5, i have to turn 4 into a fraction, turning it into y=4/1+5.
so now, i go to the X axis and start from 0 move 1 section/unit and go 4 units up on the Y axis. this is where it ends for me, what the 5 is doing there and what its supposed to do, i have no idea. :(

M is the gradient of the line. This is to say for every 1 unit across (in the x axis) you go up or down m units.
X is the independent variable, that is to say it can be any number you choose or is specified in the question
B is a constant for any equation and is the point at which the line crosses the y axis. This is because if you have y = mx + b and x = 0 then y=b
Y is the dependent variable and is affected by the value of X

And i've never seen the fraction method you mentioned, maybe its a different method of teaching i have never heard of although it makes some sense...but

I presume you know basic equation info but y=mx + b means than m lots of x plus b is the same as y. This is a just a general way of writing the equation for any straight line

Anyway if you have your example of y= 4x+5. To draw the graph you need to find a few co-ordinates of points on that line. To do this you can pick any value of x but to make it easy we will pick -2,0 and 2. So we are saying x = -2, x=0 and x=2. Just insert this value into the equation to give you y

x = -2 gives y=4(-2)+5 = -3 This means when x = -2 then y = -3
x= 0 gives y = 4(0) +5 = 5 This is the y intercept (always the case when x=0)
x= 2 gives y= 4(2) + 5 = 13

Hope this helps

lol, are you 10?


y=mx+b is the format for the equation of a line. x and y are variables. x is the independent variable, and y is the dependent variable (the value of y depends on the value of x). m is the coefficient of x, and b is a constant.

For example, lets say we have the equation y = 2x+3. 2 is the coefficient of x (or the slope), and 3 is the constant (or y-intercept). The line formed is all the x and y values that satisfy the equation, graphed on a coordinate plane.

so:

x..........y
---------
0...........3
1...........5
2...........7

if you put 0 into 'x' in our equation, the y value is 3; if you put 1 into x, y is 5, etc. the respective x and y values form coordinate pairs: (0,3), (1,5), etc that can be graphed on a coordinate plane.

You'll notice that if x is 0, then the value of y is equal to the value of b, since m times 0 = 0 no matter what m is. thus, we can easily tell the y intercept of the line from the value of b. The y-intercept is always at the point (0, b).

Now look back at our table. Notice the difference between the first two x values is 1, and the difference between the first two y values is 2. this pattern continues for the 2nd and 3rd x's and 2nd and third y's.

This allows us a new way to visualize this graphing. Instead of simply plugging in a bunch of x values and plotting the points, we can plug in one value for x, and graph the rest of the points based on the equation of the line.

so start at (0,3). Move 1 to the right (x direction), and 2 up (y direction). now we are at (1,5). It is said that the line between these two points has a slope of 2. slope is equal to the change in y divided by the change in x. in our case, the change in y (the difference between any two y values) divided by the change in x (the difference of any respective two x values) is two. Thus, the slope is 2, which is equal to m.

Moar examples:

If our line is y=5x+4:

the y intercept is 4. the slope is 5. To easily graph the line, we start at (0,4), and move to the right 1, and up 5, right 1, up 5, etc. You can also do this the other way too, left 1, down 5. These are the negative directions on the coordinate plane, but -5/-1 is still 5.

y=2/3x+1

for fractional slopes, we do something a bit different. You could go right 1, up 2/3, but that becomes annoying and inaccurate. But look: 2/3 = change in y / change in x. So we can achieve the same slope by moving right 3 and up 2.

y=-3x+5

Negative slopes are where either the change in y or the change in x is negative. So that means either left and up, or right and down, however you want to think about it. Either way the line slopes from the top left of the graph to the bottom right. Compare this with a positive slope that goes from the top right to the bottom left.


Positive slopes:

http://www.biology.arizona.edu/BioMath/tutorials/Linear/images/linear_pos_slope.gif

Negative slopes:

http://www.biology.arizona.edu/BioMath/tutorials/Linear/images/linear_neg_slope.gif

And thats the basics of it.

IR-1337, i think youre thinking a bit too far ahead at the moment

think of just y=x
x is your independent variable. y is result from the function

think of it like this.
the function, y = x is a "machine" that eats "x's" and shits out "y's". different machines process the stuff they "eat" differently.

in y = x, the function doesnt really do much. so when you feed it x= 1, y = 1.

when x=5, y=5 etc.

in y = mx + b, it mulitplies x by some value m and adds b to it.

remember, y and x and variables and will change. however, m and b are always the same.

no matter what m is, if x = 0 (that is, on the y axis), y = m0 +b = b
this is why b is the y intercept.

m is the steepness of the slope. remember, the gradient, m = rise/run. that is the change in y value divided by the x value.
-if a line travels 2 units upwards for every unit sidewards, m = 2/1 =2
-if a line travels 1 unit upwards for every 2 units sidewards, m = 1/2 = 0.5
-if a line travels 1 unit upwards for every unit sidewards, BUT TO THE LEFT (negative), m = 1/-1 = -1

to find the change in upwards change and sidewards change is easy

just get the the y-component of one point (in the form [x,y]) and subtract it by the y-component of another point
to find the change in x, just do the same thing, only for the x component.

a good formula to learn is the point-gradient formula, its used to form an equation of a line when given the gradient and one point. if your given two points but no gradient, just find the gradient with the above methods

y - y = m(x - x)
y and x are the variables in the formula so they just stay as y and x. y and x are the y and x components of your point, and m is the gradient. once youve done that, isolate the y by adding the y to the other side

eg. find the equation for a line passing through (1,4) and (5,12)
first, find m.
the change in the vertical component is
12-4 = 8
the change in horizontal component is
5-1 = 4
so the gradent
m = 8/4 = 2

now use the formula, y - y = m(x - x). you can use either points (1,4) or (5,12) and they will still get you the right answer. i will do both, for the sake for completeness
lets use (1,4)
y - 4 = 2(x - 1)
y - 4 = 2x - 2
y = 2x + 2 that is, theres slope of 2 and a y intercept of 2

now lets try (5,12)
y - 12 = 2(x - 5)
y - 12 = 2x - 10
y = 2x + 2

if you need any more explaination, just ask

Wow, you guys, this helped a lot, THANKS!

Your trying to find slope?. just use m = f'(x) = lim h -> 0 (f(x+h) - f(x))/h

And then plug it in to the equation

Your trying to find slope?. just use m = f'(x) = lim h -> 0 (f(x+h) - f(x))/h

And then plug it in to the equation

DUDE! He's having problems with y=mx+b, don't make his head explode!

MSPaint to rescue!

http://i33.tinypic.com/hsvqtl.jpg

Here:

MX = this is the steepness of the line

B = the place where it cuts the vertical line of the graph

this is the best explanation :)

Your trying to find slope?. just use m = f'(x) = lim h -> 0 (f(x+h) - f(x))/h

And then plug it in to the equation

Or he could let x and y both be functions of t, then take the partials...

dude, math blows. dont do it, then if ur teacher asks why u didnt do it, just ask when r u gonna use it. if she has a logical answer that u might actually use it, then learn it. otherwise fuck math.

btw. im not bad at math, nor am i ignorant about math. i just dont like learning shit im not gonna use.

Or he could let x and y both be functions of t, then take the partials...

Indeed. What's this y=mx+b shit they're teaching in schools today?!?!?! Why back in my day....*begin rant involving the phrase "walking home uphill both ways in a blizzard"*

btw. im not bad at math, nor am i ignorant about math. i just dont like learning shit im not gonna use.

If you think you're not going to need to use math, then you are ignorant about math. Or maybe just life.

Unless you plan on flipping burgers for the rest of your life.

If you think you're not going to need to use math, then you are ignorant about math. Or maybe just life.

Unless you plan on flipping burgers for the rest of your life.

when will i use slope or asymptotes or calculus or w/e? im not gonna be in construction or a mathematician or a scientist. but im sure as hell not going to flip burgers forever...........maybe. its up for debate right now.

I had a bit of a hard time with this too back in 8th grade..

and DarthVader, that's entirely subjective. like i just can't even put into words how retarded you are.

when will i use slope or asymptotes or calculus or w/e? im not gonna be in construction or a mathematician or a scientist. but im sure as hell not going to flip burgers forever...........maybe. its up for debate right now.

What do you plan on doing then?

Besides flipping burgers, I'm having trouble thinking of a profession that doesn't involve math.

What do you plan on doing then?

Besides flipping burgers, I'm having trouble thinking of a profession that doesn't involve math.

ur not getting my point. maybe im not being specific enough, or ur just stupid. obviously almost every profession has math integrated into it. but tell me if u can, as i said before im not gonna be a mathematician, when will i use calculus or slope or any other advanced math in a profession? im not, so why learn it? and ik that it helps increase problem solving skills, but thats not what im saying.

oh and stoned snippy. of course its subjective. its my opinion dumbfuck. im gonna have bias and be one sided.

Slope of a straight line is not advanced. At all.

I could understand if you were bitching about differential equations, but seriously, a straight fucking line? Without that you can't even do distance = rate * time stuff.

most of maths is not relevant to the maths that the majority of people need.

maybe some consumer arithmetic, algebra, etc.

but yeah, everyone should be able to do simple stuff like this when they finish school. its not particularly hard once you practise

when will i use slope or asymptotes or calculus or w/e? im not gonna be in construction or a mathematician or a scientist. but im sure as hell not going to flip burgers forever...........maybe. its up for debate right now.

Er...

As piratejoe said:

'Besides flipping burgers, I'm having trouble thinking of a profession that doesn't involve math. '

Practically any course that isn't fine arts that you go to uni for will probably require maths.

In engineering, there is never a situation where I can get around using it.

Even in the damn management course I'm taking we use it.

In accounting/econs/all those, they use it.

The machinists in a workshop I occasionally use use it.

My brother is doing fairly complex math for an entry test into medicine, and was doing fairly complex maths for his biology-related degree before that.

I just finished helping my other brother through using fairly high end maths for his honours project in programming.

My dad works in printing, and uses quite decent level maths and physics for that.

And if you do intend to flip burgers for a living, you will still need maths if you ever want to get into management of the burger flipping joint, and even if not, you will want it (at least I do) for little DIY projects around the house.

I am genuinely interested in what you want to do that doesn't involve maths at or above the level of 'y=mx+c, find the gradient'.

Unless you're in some math-intensive career like computational fluid dynamics engineering or some shit, the only time you'll ever use slope intercept form again is when you're helping your kids do the same crap that you had to do when you were their age for the same reason.

Unless you're in some math-intensive career like computational fluid dynamics engineering or some shit, the only time you'll ever use slope intercept form again is when you're helping your kids do the same crap that you had to do when you were their age for the same reason.

a math-intensive career... or any of the ones I posted above, right?

i think the only high-end subjects that dont require as much maths as usual is probably medicine (i had a friend who was IN medicine and he said he didnt use much maths), and maybe law

ur not getting my point. maybe im not being specific enough, or ur just stupid. obviously almost every profession has math integrated into it. but tell me if u can, as i said before im not gonna be a mathematician, when will i use calculus or slope or any other advanced math in a profession? im not, so why learn it? and ik that it helps increase problem solving skills, but thats not what im saying.

oh and stoned snippy. of course its subjective. its my opinion dumbfuck. im gonna have bias and be one sided.

Well have fun mowing my lawn for a living. I know I'll have fun knowing that you can't predict how much money you'll have at the end of the day, even if I tell you your hourly rate and how many hours you're going to work.

Well have fun mowing my lawn for a living. I know I'll have fun knowing that you can't predict how much money you'll have at the end of the day, even if I tell you your hourly rate and how many hours you're going to work.

your really fucking stupid. that has nothing to do with what im saying.

oh and xarf. ik slope is not difficult. i was just using it as an example along with advanced math to say that im never going to use it.

yes, nereth, but the math u and ur family does is relevant to their occupation.

your really fucking stupid. that has nothing to do with what im saying....i was just using it as an example along with advanced math to say that im never going to use it.

Lulz...never say never. You claim you're never going to use the slope formula, but what you get paid is a great example of y=mx+b, something you claim is "advanced math." You MIGHT be right about calculus, but everybody uses algebra. m=pay rate, x=hours worked, b=bonus pay, or you could let b=1.5mz, where z=hours of overtime.

Haha. Asking TOTSE for homework help. That's awesome. ^_^

your really fucking stupid. that has nothing to do with what im saying.



ORLY? Because last time I checked, calculating pay had everything to do with the topic at hand. Good luck doing that if you don't understand y=mx+b (In case you actually are this stupid, I'll spell it out for you: the amount you get paid (y) equals your hourly rate (m) times the number of hours you work (x) plus a bonus (b) if you fellate me during your lunch hour)). And that is a VERY simplistic example.

Face it DarthVader, math is central to nearly everything in our society. You simply cannot get by if you don't know at least a little math, and believe you me, y=mx+b is at the very bottom rung of that ladder.

Again, I'm going to ask you, can you name one job that produces a livable wage that doesn't use some sort of math more complex than simple arithmetic?

...

ummmm yeah....just wrote that two posts before you.

this thread shows how many people lurk this forum wishing for a question they can answer

ORLY? Because last time I checked, calculating pay had everything to do with the topic at hand. Good luck doing that if you don't understand y=mx+b

Show of hands of people who graph out their income on a chart calculating rise over run instead of just multiplying hours with rate?

Show of hands of people who graph out their income on a chart calculating rise over run instead of just multiplying hours with rate?

You don't need to calculate rise/run... rise/run=your hourly rate.

Then multiply by hours worked.

You don't realise it, but you are using y=mx+b

Yeah I realize that people use the same principle, but I was talking about the plotting on a graph specifically.

I only really use the y=mx part since there's nothing else to add.

So it's probably more like y=mx-b where b = tax liability.

dude i doubt you're even going to be able to pass high school if you cannot comprehend a simple linear equation such as y=mx+b. damn i feel sorry if they ever introduce you to even the quadratic equation, which will probably soon follow in the curriculum.

usually you just have to either plug something in or rearrange the equation to solve for a specific variable. i used to suck at math too so i know how frustrating it can be, but it will only get harder so just man up and learn it now.

btw, calculus 1 will kick your ass if you ever go to college.