![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
beandelphikiI was clearly dropped on my head as a child.
(Well, okay, I actually was. Which is an old family joke by this point. But nevermind.)
Okay, so I'm taking, "Calculus for Scientists I" this semester, yes? The first chapter of our textbook - chapter 0 - is a review/pre-calc chapter. (Yes, chapter zero. A bit like size zero, maybe?)
I am slowly slogging my way through it. The teacher isn't a great deal of help, given that he barely speaks English and pretty much assumes this is a light review for most people anyway. (And for people coming straight out of high school, I'm sure it is. Thing is, for ME, it's been about four years since I last did anything REMOTELY like this stuff.)
I've not had too much trouble up until now; it's mostly coming back to me. BUT.
Last night I was working on finding the equilibrium point between a demand curve and a supply curve, and I swear to god...I CANNOT solve this problem. What's even sadder about that is that it's an EXAMPLE problem, the textbook gives me both equations AND the answer, and I still can't figure out how to get to the answer.
Basically, the problem is this:
-50p + 900 = 100p - 600
(Solve for p.)
And WTF, I can't fucking find the bloody p! The textbook says the answer is 10, and I know this is correct because plugging it in gives me 400 on both sides. I've tripled-checked that I've copied all the numbers correctly, too.
But I can't get 10!
I MUST be doing something incredibly harebrained. Either I'm screwing up the arithmetic (because seriously guys, I can do algebra okay, but I'm a borderline remedial student when it comes to basic shit like adding and dividing), or I've got the operations wrong or something. I keep coming up with crazy shit like 30 and -3, and I am just doing something so, so wrong.
If ANYBODY has any idea what I'm doing wrong, or can post a solution, I'd be HUGELY grateful.
Edit: Oh god, the answer was like, *valleygirl* DUUUUH!
(Well, okay, I actually was. Which is an old family joke by this point. But nevermind.)
Okay, so I'm taking, "Calculus for Scientists I" this semester, yes? The first chapter of our textbook - chapter 0 - is a review/pre-calc chapter. (Yes, chapter zero. A bit like size zero, maybe?)
I am slowly slogging my way through it. The teacher isn't a great deal of help, given that he barely speaks English and pretty much assumes this is a light review for most people anyway. (And for people coming straight out of high school, I'm sure it is. Thing is, for ME, it's been about four years since I last did anything REMOTELY like this stuff.)
I've not had too much trouble up until now; it's mostly coming back to me. BUT.
Last night I was working on finding the equilibrium point between a demand curve and a supply curve, and I swear to god...I CANNOT solve this problem. What's even sadder about that is that it's an EXAMPLE problem, the textbook gives me both equations AND the answer, and I still can't figure out how to get to the answer.
Basically, the problem is this:
-50p + 900 = 100p - 600
(Solve for p.)
And WTF, I can't fucking find the bloody p! The textbook says the answer is 10, and I know this is correct because plugging it in gives me 400 on both sides. I've tripled-checked that I've copied all the numbers correctly, too.
But I can't get 10!
I MUST be doing something incredibly harebrained. Either I'm screwing up the arithmetic (because seriously guys, I can do algebra okay, but I'm a borderline remedial student when it comes to basic shit like adding and dividing), or I've got the operations wrong or something. I keep coming up with crazy shit like 30 and -3, and I am just doing something so, so wrong.
If ANYBODY has any idea what I'm doing wrong, or can post a solution, I'd be HUGELY grateful.
Edit: Oh god, the answer was like, *valleygirl* DUUUUH!
![[identity profile]](https://www.dreamwidth.org/img/silk/identity/openid.png){kind=small}
answer?
Date: 2008-09-15 01:14 pm (UTC)-50p + 900 = 100p - 600
(Solve for p.)
-50p gets moved first...
900 = (100p + 50p) - 600
900 = 150p - 600 (the letter is the same so u can add them)
900 + 600 = 150p
1500 = 150p
divide for p
1500/150 = p
10 = p
I hope thats the answer...if it is it's probably the first sum in maths i've got right for months...lol..
Re: answer?
Date: 2008-09-15 03:15 pm (UTC)This was such a case of, CAN'T BRANE TODAY, I HAVE THE DUM. I think I got so fixated on the idea that I was somehow doing the addition wrong or whatever that I completely overlooked the fact that I wasn't switching the signs when I moved things from side to side. i.e. I went to put -50p with 100p and ended up with 50p instead of 150p.
And obviously, dividing 1500 by 50 isn't going to yield you 10!
Even though my class is a full chapter ahead (I missed a couple of classes), my teacher randomly decided to do this problem on the board today. When I saw how simple it was, I died. *facepalm*
If it hadn't been for that, I'd have probably logged on here still clueless.
(no subject)
Date: 2008-09-15 07:20 pm (UTC)add 50p to both sides, etc.
(no subject)
Date: 2008-09-15 07:25 pm (UTC)like, instead of thinking of moving the -50p, just realize that if you add 50p to both sides, that will eliminate the -50p on the one side and you'll have your equation, because, really, that's what's going on. Nothing is moving, you're just doing the same thing to both sides of the equation so that it stays equal, while simultaneously making it easier for you to solve.
Same with the other operations:
add 600 to both sides
divide both sides by 150
don't move anything, you'll get all up in your head and confused. It's not theoretical, it's mechanical.
I was going to say mathematical, but I didn't think that would help in this instance.
(no subject)
Date: 2008-09-15 07:31 pm (UTC)