Maths Question

Danger Phoenix · 14 May 2006 at 16:41

Someone gave me this problem of solving x earlier, and I just couldn't do it

Code:

2x^2 + 5x = 1100

Is it even possible?

Rich_L · 14 May 2006 at 16:46

Yeah,

2x^2 + 5x - 1100 = 0

Solve using quadratic equation solver thingy. -b +- rt (etc etc)

spirit · 14 May 2006 at 16:47

Danger Phoenix said:
Someone gave me this problem of solving x earlier, and I just couldn't do it

Code:

2x^2 + 5x = 1100

Is it even possible?

its always possible, always two answers (or a double root) its whether it will be real or imaginary..

b^2 - 4ac = positive therefore real roots.. (cause c is minus so 4ac is positive)

answers can be found using x = [ -b +or- sqr(b^2 - 4ac) ] / 2a

if memory serves me right, not done any maths for a good year now, im screwed when i get to uni

MuvverRussia · 14 May 2006 at 16:48

Definitely can be solved. X is 22.235 or -24.73

p4radox · 14 May 2006 at 17:21

I get x=22.235 or x=-24.735

/edit: beaten. :mad:

ArmyofHarmony · 14 May 2006 at 17:33

hiren you're a disgrace to warwick uni

the_brainaic · 14 May 2006 at 17:40

Danger Phoenix said:
Someone gave me this problem of solving x earlier, and I just couldn't do it

Code:

2x^2 + 5x = 1100

Is it even possible?

Are you joking? You're at uni and can't even recognise a simple quadratic statement? Thats GCSE maths ffs. No wonder so many graduates are finding themselves jobless!
/rant.

SideWinder · 14 May 2006 at 17:41

the_brainaic said:
Are you joking? You're at uni and can't even recognise a simple quadratic statement? Thats GCSE maths ffs. No wonder so many graduates are finding themselves jobless!
/rant.

Yeah but is he studying Maths at Uni?

the_brainaic · 14 May 2006 at 17:42

No need - it's simple GCSE maths.

SideWinder · 14 May 2006 at 17:43

the_brainaic said:
No need - it's simple GCSE maths.

Do you HAVE to be good at Maths to get into Uni? =/

spirit · 14 May 2006 at 17:45

the_brainaic said:
No need - it's simple GCSE maths.

its not actaully on GCSE afaik, quadratics there are actually very simple not 2x^2 and usually have integer answers...

Quad formula, imaginary numbers etc isnt on GCSE.

Therefore he wouldnt be able to know if there was an answer or not @ gcse level (unless he could spot it)

Lay off.

Question is answered, no need to rail the person, people can either do maths or not, and being good at maths isnt required for everything...

Pickers · 14 May 2006 at 17:47

spirit said:
its not actaully on GCSE afaik, quadratics there are actually very simple not 2x^2 and usually have integer answers...

I did quadratics involving 2x^2 at GCSE level, though maybe I was an exception?

Etaqua · 14 May 2006 at 17:48

Quadratic formula IS GCSE work. If you're in the top set, that is, I doubt you do it in lower sets.

Edit: 2x^2, 10x^2, etc, is all done if you're in the top sets.

PinkPig · 14 May 2006 at 17:49

spirit said:
its not actaully on GCSE afaik, quadratics there are actually very simple not 2x^2 and usually have integer answers....

Rubbish, that one was as simple as they get. It's not imaginery, you plug the numbers into the formula printed at the front of the paper. Could easily come up.

spirit · 14 May 2006 at 17:51

PinkPig said:
Rubbish, that one was as simple as they get. It's not imaginery, you plug the numbers into the formula printed at the front of the paper. Could easily come up.

yes but what you fail to grasp is the fact that there are ALWAYS solutions to these equations..

Also, if he was at gcse level, he wouldn't know the formula...

Although you may be taught the formula is it examined? No. Exactly, when i did gcse, i also did p1, but not every school teaches everything.

Mr. Brightside · 14 May 2006 at 17:54

Quadratic formula is on GCSE. I've got my exams soon eeeek :eek:

Worse still I'm doing additional maths along side. We did a mock paper the other day and I got 25%. However it was a 2 hour paper and were given an hour and a quarter.

So I'm spending today going through and redoing the paper. Fun fun fun.

Wasn't aware that we get the quadratic formula given to us though, I've learned it.

spirit · 14 May 2006 at 17:55

null said:
Quadratic formula is on GCSE.

ok fair enough, i don't remmeber it being GCSE, long time ago that i guess but still unnecessary to rail him for not knowing something

DaveyD · 14 May 2006 at 17:55

The formula is was certainly tought to me at GCSE level, I'm sure of it.

Edit: Just looked at some current papers online, and yes it is used.

the_brainaic · 14 May 2006 at 17:56

The formula is on the equations sheet in the paper. All you have to do is put the numbers in and see what they churn out. You're expected to be able to use the formula in GCSE. It may seem harsh but it's absurdly simple. And even if you don't know the formula you can always google it up instead of asking on here and claiming that it can't be solved.

SideWinder · 14 May 2006 at 17:59

the_brainaic said:
The formula is on the equations sheet in the paper. All you have to do is put the numbers in and see what they churn out. You're expected to be able to use the formula in GCSE. It may seem harsh but it's absurdly simple. And even if you don't know the formula you can always google it up instead of asking on here and claiming that it can't be solved.

He said he couldn't do it, not that it couldn't be solved.

I did the Intermediate paper for Maths GCSE and we didn't do anything of that higher level but of course we did the same sort of thing. I can't think up an equation of the standard we did but we did over replacing letters with numbers, substitution etc.

Just looked up what i did, things like simultaneous equations.