Conclusion To Quadratic Equations

Solving Quadratic Equations

I'm looking for the equation of a demand curve, which is usually negative sloping, i.e. y = -x. Well, at least that is how it should look. However, I know that y = -x is a linear equation, and that's not exactly what I need. I guess it could be negatively exponential, but I just don't know. Perhaps it might help to give you a few examples of the points on the curve (points are in x:y format)

1) 1,000:400
2) 1,500:300
3) 2,400:200
4) 4,000:100

I should think that the y-intercept would be around 800. It doesn't matter very much whether the curve touches the x-axis, but I would think that the curve would start approaching it around 8,000 or 9,000.

This is actually the curve that I'm trying to find the equation for. Not only that, but then instead of having it in the format of y = ... , I would need it in the format x = ... If you could show me how to find that, I would appreciate it very much.

Answer:

The curve looks like the top right of a circle as I visualise it. You will find it difficult though to work out the exact equation of the curve.

Perhaps this may help put it in the form x=ay^2+bx+c:

y=ax^2+bx+c

y-c=ax^2+bx

You then have to complete the square:

y-c=sq( rt(a)x+(b/(2rt(a)) ) - b^2/4a (test it by multiplying it out. I may have made a mistake)

y-c+b^2/4a= sq( rt(a)x + (b/2rt(a)) )

rt( y-c+b^2/4a ) =rt(a)x + (b/2rt(a))

rt( y-c+b^2/4a)- (b/2rt(a)) = rt(a)x

<rt( y-c+b^2/4a ) - (b/2rt(a)) >/ <rt(a)>= x

A bit difficult to follow, so suggest writing it out on paper. Have used sq to mean ^2 at times and obviously rt(x) to mean the square-root of x. May be some mistakes here so apologise in advance if so, but gives the general idea on how to isolate x

The 21st Century learning professional: Training isn't learning - TrainingZone.co.uk

TrainingZone.co.uk

The 21st Century learning professional: Training isn't learning TrainingZone.co.uk, UK - Jun 18, 2008 ... only be said to be 'trained' when they have demonstrated that they have applied what they learned (remember the last time you used a quadratic equation? ...

Thursday 13: Why I Am Beginning to Like Algebra

I am as surprised at the rest of ya'll. Me? Like the dreaded evil dark power algebra? 13 Reasons why I am going toward the Dark Side.......(math being dark/eng.,ss being the light) 1. You can use alebra to figure out things you need to know like what the real interest is on your credit card debt! It's very cool. I can also explain why those "No payments for 3 years" are cons and why you should never ever do them! 2. I can now calculate out how fast two airplanes, one going south, one going w

DATE WITH JIA HUI. <3 Concert...

Haha, date with Jia Hui Darling was GREAT! ? My favourite photo in front of our favourite romantic bridge. ? She was really early rofl... So had to wait for me for 5-10 mins? Think so... She got a shock lol, said I wasn't dressing like the usual me haha. Jia Hui: "I xia4 dao4 how come got stranger come and talk to me." -_- Yay went Raffles Place's Macs (the one near the romantic bridge beside Victoria Concert Hall) for candlelight dinner cum study session rofl. I bought large fries to share f

Polynomial Root-finding with the Jenkins-Traub Algorithm

The Jenkins-Traub Algorithm is a standard in the field of numerical computation of polynomial roots, fundamentally developed as a numerical algorithm specifically for the task of computing polynomial roots. In other words, (i) because it was planned from the outset for numerical purposes rather than being simply an adaptation of an analytic formula, it is extremely robust, effectively minimizing the effects of computer round-off error, while (ii) also being extremely efficient compared to more

Reply to Keng-Wit, and a Whole Lot of More Things...

Hi Keng-Wit, Thank you so much for your *thoughtful* reply. The point numbers below correspond to those of yours, but add far more than just replying your points---in fact, my writing often just takes off in many directions unrelated to your points.... Before we begin, one point in general: The syllabus still is very much in a fluid state. So, I am very much open to revising it. (That's precisely why I put out this posting.) 1. The reason I wanted to work through both triangular (C

HELENE COOPER: IN SEARCH OF A LOST AFRICA: CONCLUSION

The attack came at dawn on Nov. 11. Some 800 African warriors advanced on the picket guards Johnson had posted at the outskirts of the settlement. The Africans opened fire; several of the guards were killed, the rest ran back to the settlement, yelling. Quickly, the African force seized control of the western part of the settlement. But instead of pressing their advantage, the African army began looting the houses they had attacked. The colonists grabbed their cannons and swung them into for

A Real Version for the Square root of -1

A Real Version for the Square root of -1 The above was conceived from the first letter of Imaginary, because the number representing the square root of -1 doesn't exist on the real number line. Pythagorus and other great Mathematicians were dumbfounded by the meaning of , yet in todays higher level Maths, is now taken for granted. However, it's true meaning seems to have been bypassed as our interpretation of it still allows history to dominate our thinking basis re . I actually dis

Permanent Link to

April 19th, 2008 A Real Version for the Square root of -1 The i above was conceived from the first letter of Imaginary, because the number representing the square root of -1 doesn’t exist on the real number line. Pythagorus and other great Mathematicians were dumbfounded by the meaning of i, yet in todays higher level Maths, i is now taken for granted. However, it’s true meaning seems to have been bypassed as our interpretation of it still allows history to dominate our think

Test

Test April 19th, 2008 A Real Version for the Square root of -1 i above was conceived from the first letter of Imaginary, because the number representing the square root of -1 doesn’t exist on the real number line. Pythagorus and other great Mathematicians were dumbfounded by the meaning of i, yet in todays higher level Maths, i is now taken for granted. However, it’s true meaning seems to have been bypassed as our interpretation of it still allows history to dominate our thinking basis

Test2

Test2 April 19th, 2008 A Real Version for the Square root of -1 i above was conceived from the first letter of Imaginary, because the number representing the square root of -1 doesn’t exist on the real number line. Pythagorus and other great Mathematicians were dumbfounded by the meaning of i, yet in todays higher level Maths, i is now taken for granted. However, it’s true meaning seems to have been bypassed as our interpretation of it still allows history to dominate our thinking basi

Test3

Test3 April 19th, 2008 A Real Version for the Square root of -1 i above was conceived from the first letter of Imaginary, because the number representing the square root of -1 doesn’t exist on the real number line. Pythagorus and other great Mathematicians were dumbfounded by the meaning of i, yet in todays higher level Maths, i is now taken for granted. However, it’s true meaning seems to have been bypassed as our interpretation of it still allows history to dominate our thinking basi