Question

Here's a really really really dumb question.
You ready?



How does one put an equation like "y = (-⅓)x - 3" into a scientific calculator?
I'm just starting to use one seeing as I need to, and there are to many buttons! xD

Answer 1

so what do you want the calculator to do with this equation?

Answer 2

I'm trying to figure out slope and whatever. Supposedly you can do that on a scientific calculator?

Answer 3

umm nope i don't think that a calculator can tell you the slope
but theres a really easy way to find the slope! :)
are you familiar with the slope intercept form of line?

Answer 4

I believe so.

Answer 5

the general slope intercept form of line is given like this-

\(\large y= \color{red}m x + \color{red}c\)

here \(\color{red}m\) is the slope of the line
and \(\color{red}c\) is the y intercept of the line

Answer 6

so suppose they give you this equation-> y=2x-1

and then they ask you the slope then to find the slope you just have to compare this equation with the slope-intercept form liek this-

slope intercept form->\(y= \color{red}m x + c\)
our equation-> \(y=\color{red}2x-1\)

now here the "2" is analogous to "m"
and we know that "m" represents the slope so that implies that "2" in the given equation represents the slope

Answer 7

Wait, I was taught \[y = mx + b\]
What is the "c" ?

Answer 8

`b` and `c` are the same !
he changed variable thats it !

Answer 9

I swear everyone else understands this slope nonsense but I never do. It just runs right off my shoulders like rusty water!

Answer 10

okay make it "c" doesn't makes any difference tho

Answer 11

Well, I'm reading what you wrote over again. This slope stuff just doesn't get into my head.

Answer 12

i can explain it in short->
in the equation of this type-> \(y=mx+b\)

what ever is in front of x (in this case it is m) is the slope of the line
and whatever is written after "mx" (in this case it is +b) is the y intercept

Answer 13

For future reference when you need to graph things
"y = (-⅓)x - 3"

type it in as
y = -x/3 - 3

if it looks exactly like that, it's fine.

y = -1/3x - 3

will also work correctly, even though the x appears to be in the denominator, it isn't.

Answer 14

\(\Huge\bf y = \color{red}{-\frac{1}{3}}x +\color{blue}{(- 3)}\)

\(\Huge \bf y = ~~\color{red}mx ~+\color{blue}{ b}\)


Simply put, the number before x is the slope in slope-intercept form. :)
Slope is -1/3 (:

I changed your equation a bit so you can see why the y-intercept is -3.
y = (-1/3)x - 3 is the same thing as y = (-1/3)x + (-3)

Answer 15

And no question is dumb, so keep on asking c:

Answer 16

the equation of a line in y intercept form appears this way:
\[ \bf y = ~~\color{red}{(some~number)}x ~+\color{blue}{ some ~number}\]

example
\[ \bf y = ~~\color{red}{3}x ~+\color{blue}{ 9}\\or\\\ y = ~~\color{red}7x
~+\color{blue}{ 8}\]

the \(\color{red}{red}\) number which is right next to \(\bf x\) is slope
and the \(\color{blue}{blue} \) number is 'y intercept'

instead of writing \(\color{red}{some ~number}\) and color coding it, people prefer the short form \(\color{red}{m}\), same with \(\color{blue}{c}\),

the letters m and c were chosen at random, so in different books you will find different letters.

Answer 17

Thank you all so much for putting your input and thoughts. I appreciate your patience with me as I try to learn it! :)