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## #1 2016-03-31 12:02:36

Hannibal lecter
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Registered: 2016-02-11
Posts: 225
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may any one tell me why the slop is 3 in the picture?
and why change in y is 3 !
and change in x is 1 !
the line is so long, how it can be that?

Last edited by Hannibal lecter (2016-03-31 12:03:20)

Wisdom is a tree which grows in the heart and fruits on the tongue

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## #2 2016-03-31 14:48:25

evene
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Registered: 2015-10-18
Posts: 272

It gives you an explanation below...

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## #3 2016-03-31 14:57:23

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Hi;

What the graph is telling you is that everytime x increases by one, y increases by three.

Slope is defined as the change in y over the change in x, so we have 3 / 1 = 3. Because this is a line this slope is the same everywhere.

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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## #4 2016-03-31 19:44:19

bob bundy
Registered: 2010-06-20
Posts: 8,415

hi Hannibal lecter

Every line will have a slope.  It is also called the gradient.  The number tells you how much the line goes up for every 1 across.

Start anywhere on the line and then count across one unit.  How far up must you go before you reach the line again.  That number is the gradient or slope.  In this question the slope is 3.

If the line is steeper you have to go up a bigger amount so the number gives an idea of how steep the line is.  A slope of 2 means the line is not so steep.  A slope that is negative means the line slope downwards as you go from left to right.

http://www.mathsisfun.com/data/straight_line_graph.html

may help with this.

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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## #5 2016-04-01 06:56:09

Hannibal lecter
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Registered: 2016-02-11
Posts: 225
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thank you very much

but I have another question please,

in this picture,

He told me try to make, like :  y = −2x + 8

how to make that in that graph?

does he mean make that equation by play with the graph?
or
in mathematically way like with pen and paper?

Sorry not my focus and my attention to some things ..  I`m Beginner.....

Last edited by Hannibal lecter (2016-04-01 07:03:20)

Wisdom is a tree which grows in the heart and fruits on the tongue

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## #6 2016-04-01 07:23:10

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

in mathematically way like with pen and paper?

You should be able to do it with pencil, paper. Everyone started off as a beginner and the fun part is you will always be one.

Do you know how to plot an equation?

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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## #7 2016-04-01 07:43:03

Hannibal lecter
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Registered: 2016-02-11
Posts: 225
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no I don`t

Wisdom is a tree which grows in the heart and fruits on the tongue

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## #8 2016-04-01 08:21:44

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

In the old days we had graph paper. Do you have some?

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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## #9 2016-04-01 09:08:40

Hannibal lecter
Member
Registered: 2016-02-11
Posts: 225
Website

sure,

if we want to make straight line by this equation{ y = −2x + 8 }
we just have to choose any value for X then find the value for Y  right?

that is easy, thank you very much for helping me

Wisdom is a tree which grows in the heart and fruits on the tongue

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## #10 2016-04-01 09:33:44

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

To make a straight line you will need 2 point. So choose 2 x's and compute the y's from them. Do you know how to plot the points on the graph paper?

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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## #11 2016-04-01 10:04:26

Hannibal lecter
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Registered: 2016-02-11
Posts: 225
Website

yes

Wisdom is a tree which grows in the heart and fruits on the tongue

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## #12 2016-04-01 10:43:16

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606