Can someone help me with substitution?

- sbuck98

Can someone help me with substitution?

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- sbuck98

##### 2 Attachments

- anonymous

hi :D ill give it a shot

- anonymous

which ones do we have to do? @sbuck98

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## More answers

- sbuck98

I kinda needed them all:(

- sbuck98

ill repost each and award a medal amd coins

- anonymous

okay thats fine :D so what do you know about substitution? do you know where to start?

- sbuck98

I have no idea

- anonymous

okay thats alright :) so ill do number 1 so just fallow along, okay?

- sbuck98

ok

- sbuck98

Could you help me with them all please though?

- anonymous

yes i will :) that was the plan all along haha

- anonymous

okay so we start with:
6x+2y=0
4x+y=-1
so the first step is to convert one to slope-intercept form (y=mx+b)

- sbuck98

Okay

- anonymous

alright so chose one to convert...

- sbuck98

6x=2y=0
so would it be y=6x+2=0?

- anonymous

close :) it would be y=-3x but you got the right idea

- anonymous

okay lets do the other one its simpler, so we star with:
6x+2y=0
4x+y=-1
we convert the second equation:
4x+y=-1
subtract 4x
y=-4x-1
correct?

- anonymous

@sbuck98

- sbuck98

Okay yes, sorry my laptop died.

- anonymous

its alright haha okay so we plug our new equation in for y into the other equation, so we get:
6x+2(-4x-1)
can you simplify?

- sbuck98

6x=2*(4x+1)

- anonymous

no you see we need to find the values of x and y so we:
6x+2(-4x-1)
distribute the 2:
|dw:1446510815383:dw|
6x-8x-2
combine like terms:
-2x-2
add 2 to both sides:
-2x=2
divide by -2:
x=-1
do you follow?

- sbuck98

yes

- anonymous

okay so now we plug that into one of the equations....
4x+y=-1
plug in for x:
4(-1)+y=-1
-4+y=-1
add 4 to both sides:
y=3
so our pair is: (-1,3)

- sbuck98

Okay

- sbuck98

Can you help me with the rest please?

- anonymous

yes so now you try the second problem, tell me your answers as you go... :) ill be right here if you need help

- sbuck98

So y=2x+-8

- anonymous

close it would be y=-1/2x -8
nice try

- anonymous

so plug that in for y in the other equation

- sbuck98

-1/2-2y=-8

- anonymous

no it would be:
3x+2(-1/2-8)=-4

- sbuck98

Okay,so I solve this?

- anonymous

yes solve for x

- sbuck98

3*8-7

- anonymous

3x+2(-1/2-8)
distribute the 2
|dw:1446512011940:dw|

- sbuck98

3x+2 1/2-8

- anonymous

3x-1x-16=-4
correct?

- sbuck98

yes

- anonymous

okayy so combine like terms

- sbuck98

so its 6x

- anonymous

no 2x-16=-4

- anonymous

add 16 to both sides:
2x=12
divide by 2:
x=6

- anonymous

so now plug in x to one of the equations

- sbuck98

3(6)+2y=-4

- anonymous

okay so now multiply

- anonymous

3(6)

- sbuck98

18+3y=-4

- anonymous

subtract 18 from both sides

- sbuck98

-11

- anonymous

18+2y=-4
subtract 18:
2y=-4-18

- sbuck98

I don't get this stuff at all:,( can you please show me how to work them

- anonymous

okay lets finish this one then ill bring someone in, okay? :) dont worry, youll do fine

- sbuck98

Can you please help me finish these questions though? I have to pass this class

- anonymous

so -4-18 is -14
so 2y=-14
divide by 2:
y=-7
our pair is: (6,-7)

- sbuck98

Thank you, Could you just explain the rest of them like you did before?

- anonymous

hold on ill bring in a friend to help you understand it :)

- sbuck98

ok

- anonymous

@MyNameIsNemo I SUMMON NIGGS!!!! haha :D

- sbuck98

Thank you

- anonymous

no problem :) @sbuck98

- MyNameIsNemo

@atreyu6s3x6 woulda' been cooler if you made me seem like a pokemon.... lol now i seem like a demon, which isnt bad, demon pokemon

- MyNameIsNemo

hm, okay anyways whats up

- anonymous

haha okay so now we're on problem 3 http://assets.openstudy.com/updates/attachments/5637fa27e4b09edab9becbb3-sbuck98-1446509118095-screenshot119.png

- sbuck98

yes

- MyNameIsNemo

this is subbing, which is pretty fun for me actually :)

- MyNameIsNemo

I love algebra!

- anonymous

she wants to further understand the process to solving it, i didn't know how to explain it any other way @MyNameIsNemo lol yea i know haha :D

- MyNameIsNemo

Okay, well :D so what dont you understand about it, ms. Ariel?

- sbuck98

Honestly, I just don't understand the whole process bc I haven't learned any of this yet.

- MyNameIsNemo

oh, is it a pre-lesson assignment?

- sbuck98

yes

- anonymous

woah i didnt know that..... hold on @sbuck98

- sbuck98

But I have a F in the class so I need to get my grade up:(

- MyNameIsNemo

ohhhhhhhh so it wont even count much for your grade if it's only a pre, darlin i cant help you on a pre-assignment, I can help you once you learn it if you need help

- anonymous

http://www.mathportal.org/algebra/solving-system-of-linear-equations/substitution-method.php
check that out, its all the steps for the process :) @sbuck98

- sbuck98

Could one of you please just help step me through the problems? I'm new to this school and don't get it.

- MyNameIsNemo

darlin, is it a pretest or pre-assessment?

- sbuck98

assesment

- sbuck98

I think, It's the one you have to take for bonus before you learn it

- MyNameIsNemo

okay, but is it a pre-assessment, like before they teach it, how new are you to the school?

- sbuck98

am I calling it the right thing?

- sbuck98

and I started a week ago

- MyNameIsNemo

how do you already have an F then .-.

- sbuck98

Because I didn't know any of the daily work they assigned me last week

- MyNameIsNemo

I'll help with ONE but you have to follow and take it like notes, then you need to do the rest alone

- sbuck98

thanks

- anonymous

look its a pre assignment so they wont grade it for correct answers, they'll simply grade it for the effort, just to see if you at least tried it, dont sweat it :)

- MyNameIsNemo

pick 1 question

- sbuck98

3

- MyNameIsNemo

okay so
5x - 4y = 14
x - 2y = -2
what do you think is your 1st step

- sbuck98

y=2x+-2?

- MyNameIsNemo

where did you get that? I want steps

- sbuck98

y=mx+b

- sbuck98

so I just filled in the #s

- MyNameIsNemo

no... ?

- MyNameIsNemo

okay 1 sec i'll show you

- anonymous

step 1: solve for x or y easiest way to remember is to convert to slope-intercept

- MyNameIsNemo

.-.

- MyNameIsNemo

sh, you just sit there and look pretty @atreyu6s3x6

- anonymous

okay :) lmao whatever, NO!! @MyNameIsNemo

- sbuck98

Can someone show me how?

- sbuck98

I know it's rearrangef to x-2*y-(2)

- anonymous

@sbucks http://www.mathportal.org/algebra/solving-system-of-linear-equations/substitution-method.php use those steps

- MyNameIsNemo

I'll write out the notes/steps and the question, you need to do the rest yourself after this okay?

- anonymous

ill be right back

- sbuck98

ok

- MyNameIsNemo

Hold on give me a few

- MyNameIsNemo

There

##### 1 Attachment

- sbuck98

I cant see it can u rotate the pic

- MyNameIsNemo

Done

- sbuck98

Can u take another picture? I cant see it

- MyNameIsNemo

Better?

##### 1 Attachment

- sbuck98

the bottom half is blurry

- MyNameIsNemo

You good?

- sbuck98

no

- MyNameIsNemo

... People have no chill... One sec

- MyNameIsNemo

Theres the bottom half

##### 1 Attachment

- MyNameIsNemo

We good?

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