Posted by **Anonymous** on Wednesday, April 25, 2012 at 10:04pm.

I have a math problem that requires me to find the focal length of a parabola using the information given on a graph. It is a standard horizontal parabola, the formula being y^2 = ax. The focus point is formula a = 4p. I know that a is positive, because the parabola opens right, however I am provided only one point on the parabola, (3, 4). The coordinate of the focus point in not given. Is there any way to solve this?

- Algebra: Parabolas -
**Steve**, Wednesday, April 25, 2012 at 11:59pm
Since it's a standard

y^2 = ax, then we know that

16 = 3a

a = 16/3

which makes p = a/4 = 4/3

- Algebra: Parabolas -
**Anonymous**, Thursday, April 26, 2012 at 4:49am
So it doesn't matter what point is given as long as it's on the parabola?

- Algebra: Parabolas -
**Steve**, Thursday, April 26, 2012 at 10:40am
That's not quite true. They gave the added information that it's a standard parabola with the x-axis as its axis of symmetry, and (0,0) as its vertex.

In general, knowing only one point on the curve is not enough, but with what they said, you know that you also have (0,0) and (3,-4) as points on the curve.

## Answer this Question

## Related Questions

- Algebra 1 parabola's - I have a graph with a parabola on it and asked to write ...
- Alg 2 (ASAP) - I have a parabola vertex (11,3) p is not given, focus pt is not ...
- College Algebra - Find the standard form of the equation of the parabola with ...
- College Algebra - Find the standard form of the equation of the parabola with ...
- Alg II/Trig - A parabola has a vertex at (0,0); a horizontal axis; and the point...
- college algebra - I have been stuck on this problem for over a week and I don't ...
- Parabola Help - by plotting the graph of parabola y=2+3x-2x^2 which 3 option are...
- math help,algebra - Okay this is what i have to do but i think i am doing ...
- math - A parabola has the equation y = 4(x-3)^2-7 Choose 2 true statements: A) ...
- math - A parabola has the equation y = 4(x-3)^2-7 Choose 2 true statements: A) ...

More Related Questions