Algebra question

[Barry Scott]

I helped a friend's son with his Algebra the other day and came a cropper on a question. I'm telling myself it's because i haven't done it for 15 years, but it seemed really basic stuff and it's literally given me sleepless nights.

Right, it's a simple case of rework it or whatever it is you call it, to make the equation X=

a^2/x = yz

So, both sides, multiplied by X.

a^2 = x(yz) and then it looks as though you should divide by yz, but this seems a bit illogical to me, as i see it as this mess:

a^2/yz = x(yz)/yz

Although i believe it should be as so, but it just seems too clean:

x = a^2/yz

So, please tell me why dividing x(yz)/yz is x. With numbers it's obvious, but maybe it's just me, i really do not like this answer. It just seems wrong to me and has put my precious little pedantic nose right out of joint.

[Ginginho]

What if you just multiple by a^2?

Doesn't that become:

x = yz(a^2)?

I haven't done algebra for fucking ages, and was shit at it then.....

[reeves4england]

What if you just multiple by a^2?

Doesn't that become:

x = yz(a^2)?

I haven't done algebra for fucking ages, and was shit at it then.....

No

x = a^2/yz .... so if you multiply by a^2 then you get...... x(a^2) = a^4/yz

Barry's question is why does x(yz)/yz = x

Try thinking of it this way: if y and z are two numbers, they just make another number, which we can call w. w=yz.

x(w)/w = x

x times w, then divided by w, = x

In the same way that 5 times 2, then divided by two, = 5

[Samdy Gray]

I know this is your very basic GCSE level linear equation, but after spending my evening learning and trying to remember redemption yield formulas my brain is now fucked after trying to work out that equation.

I better call it a night.

[Nijholts Nuts]

Youre right, all the way because when it becomes a^2 = (yz)x/yz the denominator and the numerator which are (yz) cancel each other out. It's like saying 2x/2, if you forget the x for a minute it leaves you with 2/2 which makes 1,
1x = x

[donkey]

I may be wrong, and I've had a couple of beers, but I'll have a go...

a^2/x = yz

a^2= xyz

a^2/yz = x

Edit:  Realised you've done it like that...I'll have another beer.

[Nijholts Nuts]

I may be wrong, and I've had a couple of beers, but I'll have a go...

a^2/x = yz

a^2= xyz

a^2/yz = x

Tick , or well thats what I got anyhow.

[4D]

I helped a friend's son with his Algebra the other day and came a cropper on a question. I'm telling myself it's because i haven't done it for 15 years, but it seemed really basic stuff and it's literally given me sleepless nights.

Right, it's a simple case of rework it or whatever it is you call it, to make the equation X=

a^2/x = yz

So, both sides, multiplied by X.

a^2 = x(yz) and then it looks as though you should divide by yz, but this seems a bit illogical to me, as i see it as this mess:

a^2/yz = x(yz)/yz

Although i believe it should be as so, but it just seems too clean:

x = a^2/yz

So, please tell me why dividing x(yz)/yz is x. With numbers it's obvious, but maybe it's just me, i really do not like this answer. It just seems wrong to me and has put my precious little pedantic nose right out of joint.

What job would this help to get? 

[Nijholts Nuts]

Maths Teacher

[4D]

I did A level maths (many years ago) what the hell is the ^ ?

[Nijholts Nuts]

to the power of

a^2 = a squared

[Simon Pieman]

I did A level maths (many years ago) what the hell is the ^ ?

And they say shit is getting easier.

[4D]

^ wasn't "to the power of" when I was at school

[reeves4england]

What job would this help to get? 

You need to be able to do that stuff if you want ANY kind of qualification or job which relies on mathematical analysis really

[Barry Scott]

No

x = a^2/yz .... so if you multiply by a^2 then you get...... x(a^2) = a^4/yz

Barry's question is why does x(yz)/yz = x

Try thinking of it this way: if y and z are two numbers, they just make another number, which we can call w. w=yz.

x(w)/w = x

x times w, then divided by w, = x

In the same way that 5 times 2, then divided by two, = 5

Yeah, this was how i clarified it in my mind, switch it for numbers and all is well. It's probably because i haven't touched algebra for ages, but i just find x(yz) divided by yz too, i dunno, convenient. I think i think of x(yz) as it's own entity; a completely new variable, that then becomes indivisible by yz in any manner that brings simplification.

I'm almost tempted to fish out my old maths books, because it now seems to make perfect sense and i'm questioning why i was so puzzled by it.

What job would this help to get? 

Algebra teacher.