+0

# SLOPESSS

0
508
13
+314

How can you tell if a slope is negative or positive? For instance in this question (btw I know what to fill in the second blank):

How can I tell? I NEED A SIMPLE EXPLANATION IM DUMB.

Sep 2, 2017

#1
+558
0

If the line is going up, it's positive. If the line is going down, it's negative.

Sep 2, 2017
edited by Gh0sty15  Sep 2, 2017
edited by Melody  Sep 2, 2017
edited by Melody  Sep 2, 2017
edited by Gh0sty15  Sep 2, 2017
#3
+101044
+1

All lines that are not horizontal or vertical go up on one end and down on the other end ://

Melody  Sep 2, 2017
#6
+558
0

Oops. Sorry Melody. Sorry ISmellGood. I forgot about those...and many other things... hmm...  :(

Gh0sty15  Sep 2, 2017
edited by Gh0sty15  Sep 2, 2017
#9
+314
0

It's okay :)

ISmellGood  Sep 2, 2017
#10
+558
+2

My brain needs a few adjustments... Making too many mistakes in math. It might take a while for me to get back on track. Sorry everyone.

Gh0sty15  Sep 2, 2017
#12
+558
+1

What I actually meant was if the line goes like this:  /, then it has positive slope.

If the line goes like this: \, then it has negative slope.

Sorry again...

Gh0sty15  Sep 2, 2017
#13
+101044
+2

You do not need to be appologetic. It is not a big deal :)

Melody  Sep 2, 2017
#2
+101044
+2

Hi,

Firstly you are not dumb, :)

Dumb people do not bother to ask good questions :)

First .. is the gradient positive or negative. ??

Lines go for ever, if you think about any line,

it may eventually be in the top right corner where the + is    in which case the gradient will be positive.

OR

it will eventually be in the top left corner where the - is   in which case the gradient will be negative.

So does your line have a positive or a negative gradient ?

Now, I think your line goes through the two points (0,-9) and (3,3)

Draw a right angled triangle between these two known points. One side has to be parallel to the x axis and the other parallel to the y axis, like I have done.

gradient is   rise/run     To get from the bottom point to the top one you have to rise 12 and run along 3

SO  the gradient is   + (because the line heads off to the top right corner)  12/3  =  +4

The y intercept is -9, you said you already knew that.

b=-9

m=4

line:           y=mx+b

this line      y=4x+-9

y=4x-9

I have redrawn you graph so I can explain better

Sep 2, 2017
#5
+314
+1

Thank you!

ISmellGood  Sep 2, 2017
#4
+7499
+1

When the line looks like a backslash "\", its slope is negative.

When the line looks like a slash "/". it slope is positive.

Sep 2, 2017
#7
+314
+1

Thanks, is it always that way?

ISmellGood  Sep 2, 2017
#8
+7499
+1

Yes :D

also, when the line is horizontal, its slope is 0,

when the line is vertical, its slope is not defined, or you can say its infinity.

MaxWong  Sep 2, 2017
#10
+314
0

Oooooooh!

ISmellGood  Sep 2, 2017