#How do I solve equations?

285 messages · Page 1 of 1 (latest)

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rare spindle
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I don‘t know where to start

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And I don‘t know why would you wanna solve an equation

vocal eagle
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Firstly what grade are you in

rare spindle
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7

vocal eagle
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Welp alright

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Uh so when we're solving equations

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What we want to do is isolate unknown terms on one side

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And constants on the other side

rare spindle
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Okay

vocal eagle
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Sounds a bit abstract rn but I guess I'll give an example

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Let's say we have 2x+3=x+2

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Let's try to get x terms on the left and constants on the right

rare spindle
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So like 2x+x=3+2?

vocal eagle
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No not really

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So firstly what we make use of

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When we solve equations

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Is whatever we do on the left side of the equation

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Also happens on the right side

rare spindle
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Why tho?

vocal eagle
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We know that 5=5

rare spindle
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It wouldn‘t be the same equation then

vocal eagle
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Actually nvm bad example

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Let's say you two people had the same amount of apples

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And you stole the same number of apples from each of them

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Would the two people still have the same amount of apples?

rare spindle
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Yes ig

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And you can add apples as well, can‘t you?

vocal eagle
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When we use the = sign we're saying that both expressions on the left hand and right hand side of the equal sign are well equal

vocal eagle
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If the same amt was added to each person

rare spindle
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Okay

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Understood

vocal eagle
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So 2x+3=x+2

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Let's subtract x from both sides

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This brings x to the left hand side

rare spindle
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But we don‘t knoe what x is

vocal eagle
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This then becomes
x+3=2

vocal eagle
rare spindle
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Oh okay

vocal eagle
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2x-x=x

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Don't have to know what x is

rare spindle
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But can u just subtract both sides 2 so 2x becomes x?

vocal eagle
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That's what we're doing😭

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This then becomes
x+3=2

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From here can you finish the problem

static quarry
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Perhaps I might be able to help?

rare spindle
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Hi

static quarry
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Hi.

vocal eagle
rare spindle
static quarry
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Okay, so here's the thing. What is an equation?

vocal eagle
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Just don't use too complex definitions please

rare spindle
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Wouldn‘t it be like 2x+3=x+2 and then subtract borh sides 2 so we get x+3=x and then minus x so 3=0

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Oh wait

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Ye nvm

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Pls continue

static quarry
rare spindle
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Find x?

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That what our teacher told us

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Find an x such that both sides are like same?

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Are you guys still there?

vocal eagle
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The class is just on the topic of equations

static quarry
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It's an assertion that two expressions have equal value.

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When we say, for instance, that 3x + 7 = 4 - 9x, we're saying that 3x + 7 and 4 - 9x are both numbers, and they're the same number.

rare spindle
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Numbers?

static quarry
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Yes.

rare spindle
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But there is an x

static quarry
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The x is a number.

rare spindle
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So it‘s a random number?

static quarry
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No.

rare spindle
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What are we trying to find?

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X right

static quarry
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...yes...

rare spindle
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So if x is a number why is 4- 9x not a number

static quarry
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...it is a number. I said it was a number, you said it wasn't.

rare spindle
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Oh sorry my bas

static quarry
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Or expressed confusion.

rare spindle
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So you are tyring to find an x such that both sides have euqal value?

static quarry
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Right.

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And the way that we do that is by transforming the equation.

rare spindle
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How do we transform it tho?

static quarry
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We make new equations that must be true if our starting equation is true.

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For instance, if a = b, then a + c = b + c, right?

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Where a, b, and c are all numbers.

rare spindle
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If two people have the same amount of apples and you give them 100 apples both they both still have the same amount?

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Is it what u r trying to say?

static quarry
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...sure.

rare spindle
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Okok

static quarry
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Also, if a = b, then a - c = b - c.

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And a * c = b * c.

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And a / c = b / c (if c =/= 0).

rare spindle
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Hmm

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One second I have ti write it down

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Okay done

static quarry
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Okay, so.

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Consider the equation 2x - 10 = 20 - x.

rare spindle
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-2x on both sides?

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@vocal eagle said to seperate them

vocal eagle
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Well this is just the initial equation

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And also don't ping me rn😭

rare spindle
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Okay my bad

static quarry
rare spindle
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Okay

static quarry
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And we do this using the equation rules I just told you about.

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(For the record, we can prove them, but the proof would probably go way over your head at this stage in your education.)

rare spindle
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If someome has 10 apples

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And the other one aswell

static quarry
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That's not a proof.

rare spindle
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But it‘s logical

static quarry
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Not really. I mean, it's good if you have a way to think about it that helps you come to terms with it, but that doesn't make it a proof.

rare spindle
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How do u actually proof it

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I may understand it

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Or atleast I wanna give it a try

static quarry
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You're not gonna understand it.

vocal eagle
static quarry
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Like, we literally have to go through Zermelo-Fraenkle set theory to Peano arithmetic to Dedekind cuts and it's a slog.

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Like, it's very fascinating, but at your age I'm not sure you even have the brain architecture yet to understand or appreciate it.

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And it certainly won't help you learn the material in front of you.

rare spindle
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But Not much

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Like A={1;2}

static quarry
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That's not set theory, that's just naming a set.

rare spindle
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What about the intersection of two sets

static quarry
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We're getting far afield.

rare spindle
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Draw to circles

static quarry
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Let's refocus back on the equations.

rare spindle
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Okay

static quarry
rare spindle
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-2x?

static quarry
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...what do you mean by that?

rare spindle
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On both sides

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Substract 2x

static quarry
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Hmm. Well: 2x - 10 - 2x = 20 - x - 2x

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That is certainly still a true equation.

rare spindle
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Can you atleast send a picture of your magic math theory

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I‘m rlly into math

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I wanna understand set theory

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Plsss

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Only once

static quarry
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No. It's not in a picture, and it's not magic.

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And it's way way way too long.

rare spindle
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How long?

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2 pages?

static quarry
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...no, like a week.

rare spindle
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What is the hardest topic in math?

static quarry
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Getting you to stay on topic.

rare spindle
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Oh

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Okay Imma focus now

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Sorry

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Pls go ahead

static quarry
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It's fine. Your enthusiasm is appreciated, it's just not very constructive if it's not directed at the problem in front of you.

static quarry
rare spindle
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2x-2x

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Is

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0.1

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Jk

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0

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Or isn‘t it 0

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?

static quarry
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Yes.

rare spindle
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Okok

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So we get -20=x?

static quarry
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...no.

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How would we get that?

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Take it step by step.

rare spindle
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Oh brain lag

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Uhm

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-10=20-x-2x

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And then

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-20x

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No no

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-20

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To seperate the numbers and the alphabet

static quarry
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Okay, stop.

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We have -10 = 20 - x - 2x, right?

rare spindle
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Yes

static quarry
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Can we simplify this before doing anything else?

rare spindle
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We can bring the 20 on the other side

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Uh wait no

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I see

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-x-2x is -3x

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So we get -10=-20-3x

static quarry
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Right.

rare spindle
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And now +20?

static quarry
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Why?

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Okay, stop.

rare spindle
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To bring the -20 on the other side

static quarry
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I need you to be writing this all on paper.

rare spindle
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I‘m sure I can do it in my head

static quarry
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You're already making mistakes.

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This is what paper is for.

rare spindle
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Can I write on my iPad?

static quarry
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What were you writing those notes I gave you before on?

rare spindle
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On my pc

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But my dad took it a way a few min ago

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So I switched on my iPad

static quarry
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Look, write it wherever the hell you want to, just write it.

rare spindle
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Okok

static quarry
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Showing your work, visibly, all in one place, one step after another, is important.

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Our initial equation is 2x - 10 = 20 - x.

rare spindle
static quarry
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Okay.

rare spindle
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-20?

static quarry
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Try it.

rare spindle
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Like that?

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In theory

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If you plug in 10 for x

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Both sides have to be equal

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Right?

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Oh it works

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Yay

static quarry
rare spindle
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Huh

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But the solution is correct

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Hmm

static quarry
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Because you made two mistakes that cancelled out.

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See, you should've divided by -3, and that's basically what you did, but what you wrote is division by 3, and that you did incorrectly.

rare spindle
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Ohhh I see

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3/-3 is -1

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And 30/-3 is -10

static quarry
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Right.

rare spindle
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So you get -10=-1*x

static quarry
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Yes.

rare spindle
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And only Number that satifies the equation is 10

static quarry
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Right.

rare spindle
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I understand it now

static quarry
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Glad to help.

rare spindle
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Can you teach me more math

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Something else

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Plss

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I would really appreciate it learning from genuises

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Or higher ranks

timid lark
rare spindle
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Not really

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Js wanna learn math

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Like further math

timid lark
static quarry
rare spindle
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And I wanna solve it

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But yet I don‘t have the tools

static quarry
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This is gonna be the Riemann hypothesis or something, isn't it?

rare spindle
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I‘ve seen it on the other math server

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This one

timid lark
rare spindle
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But one day i wanna learn it

timid lark
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this is way beyond a 7th grade level, much less high school

rare spindle
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Maybe 4 months

timid lark
rare spindle
timid lark
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what topics do you want completed within 1 month?

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2 months?

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3 and a half?

rare spindle
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Maybe calculus

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I‘ve done some research

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But

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I don‘t know how much it is

timid lark
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it is a lot.

rare spindle
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Would u say it is possible to learn calculus within 4 months

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Like only applying

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Not actaully to a 1 week long proof

static quarry
rare spindle
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Wdym

static quarry
# rare spindle Wdym

I mean no, it's not possible for a seventh grader to learn calculus within 4 months.

timid lark
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i still have to cover calc III, in addition to linear algebra.

rare spindle
timid lark
static quarry
rare spindle
timid lark
rare spindle
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May I ask how old are you

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Techie

prime prairieBOT
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wrong channel bozo. Go to #geonosidan-prison-complex