algebra

[frosty wolf]

i cant solve this

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[frosty wolf]

@viral glacier

help me bro

tell me your method

[rain ether]

his method was the same as mine lol

[frosty wolf]

he started by doing minus

and i dont know how you got Y

[rain ether]

ok

[frosty wolf]

i literally tried any possible way i dont know how you got y

its like if your making stuff up

[viral glacier]

Ok so this is what I said.

[rain ether]

ooh making stuff up

very fun

[viral glacier]

3x + 2y = 15.
10x - 4y = 2.

Add both.

13x -2y = 17.

13x = 17 + 2y.

And we get x = (17+2y)/13.

[viral glacier]

3x = 15 - 2y.

Here x = (15-2y)/3.

And 10x = 2 + 4y.

So x = (2+4y)/10.

We got three values for how x can be in y terms.

From there I hope you can solve for x.

[smoky bobcat]

@viral glacier I don't know what you are trying to do but most of the steps in your calculations won't get you any closer to the solution. Why don't you explain a bit more so @frosty wolf can see how to solve this type of question?

[viral glacier]

What do you mean?

We have 3 different values for x now.

We have x = (15-2y)/3 = (2+4y)/10 = (17+2y)/13.

Cross multiply.

30 = (15-2y)(2+4y).

[smoky bobcat]

It seems like you can't decide if you are going to solve the system by adding,substituting or setting two equations equal. Instead of that you do everything of that at once but can't find the value of x. You could have solves the system right in your first step by adding the first equation two times.

[viral glacier]

30 = 30 + 60y - 4y -8y^2.

[smoky bobcat]

Deriving three expressions is absolutely pointless and won't get you anywhere.

[viral glacier]

May I continue?

[viral glacier]

Actually you have a point.

3 isn't necessary.

I was going overboard with that.

[frosty wolf]

okay

i just dont know how to find Y

thats it

[smoky bobcat]

The point is that your way of solving this system is not a good way to get a lot of points in a test. You have used methods to solve a system of equations but using three of them at once will only cause confusion.

[frosty wolf]

im still very confused

[smoky bobcat]

Now you can continue. But please do it in a structured way so that a student can understand your solution and reproduce it in a test.

[viral glacier]

Schlaumau it seems you are better at teaching, I would recommend you doing that.

I have to go anyway.

Plus I can't explain well in this condition.

[smoky bobcat]

Okay.

Did you learn any specific method in school @frosty wolf?

[frosty wolf]

no

because i dropped off for 8 months

about that

and i lost allot

[left owl]

isnt this just x=2 and y=9/2 you just multiply the top equation by two, then add the two together for 16x=32 -> x=2 and then solve for y

[smoky bobcat]

It is.

[frosty wolf]

exactly but why do you have to do 32

why 16 x 2

[left owl]

well you add the two equations together to cancel out one of the variables

its a lot easier when you only have to solve for one

[frosty wolf]

yea but for the answer of y you need to do

144 devided bu

by

[smoky bobcat]

@left owl do you think it is helpful when we are both talking at the same time?

[frosty wolf]

16

[left owl]

bruh ok then i'll go

[frosty wolf]

why did you multiply 16 tho

i just want to know that

[smoky bobcat]

$$6x+4y=30$$
$$10x-4y=2$$

When solving a systems of equations we are allowed to add two equations to another. Our goal by doing that is to eliminate one of the variables so we are left with an equation in a single variable. Another thing we are allowed to do is that we can multiply a line by a constant factor.

[frosty wolf]

ok

[jaunty cypress]

Schlaumau

[smoky bobcat]

Do you see what I have done here?

[frosty wolf]

wait

yes

i see

2x both

of them

[smoky bobcat]

I only multiplyed the first one by two

I didn't change the second one

[frosty wolf]

how

because

you got 6x and 4y

what do you do after anyways

i understand this

next step?

[smoky bobcat]

I just told you that we can add two equations by adding their left sides and setting that equal to the sum of their right sides. What would we get if we do that here?

If you don't know you can tell me

[frosty wolf]

i dont know

reading text is more confusing

then someon talking so do it step by step

with me

[smoky bobcat]

By adding the left sides we get
$6x+4y+10y-4y$

[frosty wolf]

yes after

[smoky bobcat]

And by adding the right sides we get 30+2=32

Can you see how this one simplifies?

[frosty wolf]

where did you get 40 from

[jaunty cypress]

Schlaumau

[smoky bobcat]

I meant 4

Had a 0 to much there

[frosty wolf]

oh ok

after

what do ido

[smoky bobcat]

Now 6x+10x=16x and 4y-4y=0 so the left side becomes 16x

[frosty wolf]

and after

what do we

[smoky bobcat]

Now we have 16x=32

Finding x now is easy isn't it?

[frosty wolf]

but why 32

why do you double 16

thats whats confusing me

that's exactly where im stick

stuck

[smoky bobcat]

When we added the right sides here we got 30+2=32

I didn't just double the 16.

[frosty wolf]

so where did you get 16 from

nvm

sorry

now what do i do

[smoky bobcat]

Did you learn how to solve linear equations?

[frosty wolf]

no

i dont know any algebra

not even 1%

[smoky bobcat]

$16x=32$

[jaunty cypress]

Schlaumau

[viral glacier]

What could x be 🤔.

2763?

[smoky bobcat]

Okay. When solving equations we are allowed to do the same operation on both sides of the equation. As an example here we are allowed to divide both sides by 16.

[frosty wolf]

i dont know

[viral glacier]

Oh you actually don't?

[frosty wolf]

no i dont

i actually dont

[smoky bobcat]

After that we get $x=\frac{32}{16}=2$

[jaunty cypress]

Schlaumau

[viral glacier]

16x/16 = 32/16.

[frosty wolf]

and X = 2

but y

is 4.5

[viral glacier]

16x = 32.

[frosty wolf]

how do i get to 4.5

[smoky bobcat]

We are now going to substitute our value of x in one of these equations

By choosing the first one we get $6\cdot2+4y=30$

[jaunty cypress]

Schlaumau

[smoky bobcat]

Do you understand that so far?

[frosty wolf]

no

where did 6 come from

[smoky bobcat]

We know that 6x+4y=30

[frosty wolf]

oh at the begging

beggining

yea

[smoky bobcat]

We have just found out that x=2

Because of 6*2=12 we now have $12+4y=30$

[jaunty cypress]

Schlaumau

[frosty wolf]

wait

can i show you the way i did it

and maybe tell me

[smoky bobcat]

Sure

[frosty wolf]

how to get to y

idk how to get Y

after this

i devided 10 by 2 and 4 by 2

them

[smoky bobcat]

I see

[frosty wolf]

2 devided by 2 wich gave 1

then

i put all of them

and i got the X answer

now how do i get Y

any idea?

[smoky bobcat]

You have to substitute the value you have found for x into one of the equations you already know

You wrote 5x-2y=1

[frosty wolf]

yes

[smoky bobcat]

Now you know that x=2 so $5\cdot2-2y=1$

[jaunty cypress]

Schlaumau

[smoky bobcat]

$10-2y=1$

[jaunty cypress]

Schlaumau

[smoky bobcat]

Is everything clear so far?

[frosty wolf]

what does the dot mean

[frosty wolf]

i dont know in algebra im far back

what does it mean

[smoky bobcat]

$5\cdot2=10$

[jaunty cypress]

Schlaumau

[smoky bobcat]

"times"

[frosty wolf]

oh

ok

tysm

[smoky bobcat]

By adding 2y to both sides here we get 10=2y+1

[frosty wolf]

yes

and now what do i do

[smoky bobcat]

We now want to remove the 1 from the right side so we subtract one from both sides

After that we have 9=2y

[frosty wolf]

so 10-1

[smoky bobcat]

Yes

[frosty wolf]

and after

what do ido

[smoky bobcat]

Which number times two is equal to nine?

[frosty wolf]

9x1?

idk 😭

ohh times 2

i have to devide

it

[smoky bobcat]

We divide both sides of the equation by two

[frosty wolf]

so i do 9 devided by 2

[smoky bobcat]

Yes

Which is equal to 4.5

[frosty wolf]

so the answer is 4.5

[smoky bobcat]

That's how you get y.

[frosty wolf]

thank you so much

holly

you dont understand

im stuck here for 3 hours

i was watching yt and even maths solving application

none helped

your the only one that helped me

thank you so much

[smoky bobcat]

That's nice

No problem

[frosty wolf]

if i need help can i ask you in the future?

[smoky bobcat]

You can ping me then. But I cant guarantee that im going to answer immediately. But there are many other competent helpers here who you can also ask.

[frosty wolf]

ok ty