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Topic: How would you find the parabolas determined by points {-1,2}, {1,-1},
{2,1}?

Replies: 5   Last Post: Jan 6, 2014 7:58 PM

 Messages: [ Previous | Next ]
 Hetware Posts: 148 Registered: 4/13/13
Re: How would you find the parabolas determined by points {-1,2},
{1,-1}, {2,1}?

Posted: Jan 5, 2014 10:43 PM

On 1/5/2014 10:21 PM, Hetware wrote:
> Given the three points (-1,2), (1,-1), and (2,1). (a) Find a parabola
> passing through the given points having its axis parallel to the x-axis.
> (b) Find a parabola passing through the given points having its axis
> parallel to the y-axis.
>
> I set up the equation
>
> (y-k)^2=4p(x-h)
>
> and substituted the given ordered pairs and crunched the numbers. It
> became (rather) messy, but I arrived at the given solution. I'm
> wondering if there is a more efficient approach to the problem.
>
>
> 7(y^2)-3y+6x-16=0
> 7(x^2)-9x-6y-4=0

Sorry. I neglected to give credit. The problem is from Thomas,
Calculus and Analytic Geometry, 1953.

Date Subject Author
1/5/14 Hetware
1/5/14 Hetware
1/6/14 Port563
1/6/14 Virgil
1/6/14 Port563
1/6/14 RGVickson@shaw.ca