Question

MASSIVE HELP NEEDED PLEASE

Answer 1

basically i am homeschooled and i am cramming tonight so i can take my math exam tomorrow or i fail

Answer 2

Too many questions at once!

Answer 3

Lets look at the first once

Answer 4

one*

Answer 5

and if i fail i cant go back to regular school in september

Answer 6

okay

Answer 7

So for the first one, you have a line right? To find the slope, take any two points and use the formula of slope I showed you earlier, this one: \[ m = \frac{ y_{2}-y _{1} }{ x _{2}-x _{1} }\]

Answer 8

but there 4 points

Answer 9

Doesn't matter, take any two points, it'll work ;)

Answer 10

ok so (-2,0) and (-5,0) those are correct right?

Answer 11

or is it (0,-2) and (0, -5) ?

Answer 12

You read the graph (x,y)

Answer 13

(-2,0) and (-5,0)

Answer 14

And there is no (0, -5)

Answer 15

** -6

Answer 16

That's (-6, 0)

Answer 17

okay

Answer 18

Lets use (-6,0) and (0,-2)

Answer 19

so i do -2 - (-6)

Answer 20

and 0-0 which is still 0

Answer 21

?

Answer 22

oh wait

Answer 23

would it be 0 - (-6) and 0 - (-2)

Answer 24

0-(-6) is right, but it's -2-(0)

Answer 25

You should really write this out on a piece of paper, or you won't remember.

Answer 26

i am

Answer 27

Ok cool

Answer 28

So the slope will be?

Answer 29

6/ -2 ?

Answer 30

Yeah that = ?

Answer 31

-3

Answer 32

Good job, so, before we go ahead I want to tell you slope intercept looks like y = mx+b form, where m is your slope, b = y - intercept (where the line crosses the y - axis).

Answer 33

wait so how would i write that in slope intercept form?

Answer 34

\[y-y _{1}=m(x-x _{1})\]

So now use point - slope form, though there's another way, lets just use this.

Answer 35

Do that first

Answer 36

how :(

Answer 37

No worries, ok we were given points (-6,0) and (0,-2) right?

Answer 38

mhmm

Answer 39

Just plug in y1 and x1 for now and show me what you get

Answer 40

and the slope

Answer 41

this is giving me a head ache ugh but ummm

Answer 42

y1 =0

Answer 43

Mhm I think this website might be better for you, it will show you the steps better, since there is only so much I can do: http://www.mathsisfun.com/equation_of_line.html this will tell you all you need to know.

Answer 44

ive gone over this a million times

Answer 45

i just dont understand it

Answer 46

ok:(

Answer 47

One sec

Answer 48

Yeah, it's fine haha. Alright, so what part are you having trouble at understanding?

Answer 49

how to put something into slope form

Answer 50

Well this is the slope - point form,

\[y-y _{1}=m(x-x _{1})\]

and what ever our (x1, y1) were we plug it into x1 and y1 in the equation so lets say it was (0, -2) we just do this

\[y-(-2)=m(x-0)\]

\[y+2=m(x-0)\]

and then just distribute

\[y+2=mx+0\]

solve for y,

\[y=mx-2\]

Answer 51

Our slope should be -1/3 actually now that I look at the graph we just mixed up our coordinates :) so your answer should be \[y=-1/3x-2\]

Answer 52

you are honestly a life saver

Answer 53

Hey np, does that make sense?

Answer 54

yes, it does

Answer 55

im writing it all down now

Answer 56

and i just have one more question... Write an equation of a line in slope intercept form that is perpendicular to y = -4x -2 and passes through the point (-16, -11).

Answer 57

no idea how to do that one

Answer 58

Awesome, the thing I figured our slope was wrong, was because look at the graph,

the slope is basically telling us this,

\[m = \frac{ Rise }{ Run } = \frac{ y_2-y_1 }{ x_2-x_1 }\]

So how did I know from the graph? Let me draw it for you.

I used those two points, and y - intercept where the line crosses the y - axis, is the y - intercept (b) in y=mx+b, and looking at the graph slope tells us, y (rise) how many coordinates up and down, and run x (run) left and right, you see how the next point is 3 coordinates to the right of and 1 coordinate down, so looking at the slope formula we would say 1 down, and 3 right, so -1/3.