Algebra: Parabolas

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?

  1. 👍
  2. 👎
  3. 👁
  1. Since it's a standard

    y^2 = ax, then we know that

    16 = 3a
    a = 16/3

    which makes p = a/4 = 4/3

    1. 👍
    2. 👎
  2. So it doesn't matter what point is given as long as it's on the parabola?

    1. 👍
    2. 👎
  3. 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.

    1. 👍
    2. 👎

Respond to this Question

First Name

Your Response

Similar Questions

  1. CALCULUS

    If you could give an explenation with the answers, that'd be wonderful so I actually know how to solve similar problems in the future. :) Thank you so much! 1. A convex lens with focal length f centimeters will project the image

  2. Physics

    1. A concave mirror forms a real image at 25cm from he mirror surface along the principal axis. If the corresponding object is at a 10cm distance, what is the mirror's focal length? 2. A woman looking in a makeup mirror sees her

  3. precalculus

    one section of a suspension bridge has its weight uniformly distributed between twin towers that are 400 feet apart and rise 90 feet above the horizontal roadway. a cable strung between the tops of the towers has the shape of a

  4. precalculus

    Find the focus, directrix, and focal diameter of the parabola. x2 = 5y focus (x, y) = 0, 5/4 directrix:y=-5/4 focal diameter=5 Sketch its graph? my answers seem to be correct but i cannnot sketch the graph correctly.

  1. Physics HELP

    an object 3.00 cm high is placed 20.0cm from a convex mirror with a focal length of magnitude 8.00 cm. Find the position of the image. (Im using 1over20.00 + 1overQ = 1over-8.00) and the answer is q= -5.71cm. can someone tell how

  2. Calculus: Centers of Mass

    Find the centroid of the region in the first quadrant bounded by the x-axis, the parabola y^2 = 2x, and the line x + y = 4. I've graphed the function, and it looks like a triangle with one side curved (the parabola). I'm not quite

  3. Math

    A hyperbola has a vertical transverse axis of length 6 and asymptotes of y = (2x/5)+2 and y = (-2x/5)-4. I am having trouble finding the focal length. I mean I think I've found it, but apparently it's incorrect. c = sqrt(a^2+b^2)

  4. precalculus

    Find the focus, directrix, and focal diameter of the parabola. y2 = 8x

  1. s

    The topic I will write about is my favorite subject in school, Math. Do you like Math, because I sure do! Math is cool because it is interesting in many ways. You can add, subtract and even divide! You can do many things with

  2. science

    Which of the following adjustments would cause an image to change from real to virtual? a)moving the object from the focal point of a converging lens to a position inside the focal length b)moving the object from the focal point

  3. Algebra 1

    Solve by completing the square: A rectangular patio has a length of (x + 6) m, a width of (x + 8) m, and a total area of 400 m2. Find the dimensions to the nearest tenth. Please help me with this math problem. Thanks so much.

  4. physics

    (a) A concave spherical mirror forms an inverted image different in size from the object by a factor a > 1. The distance between object and image is d. Find the focal length of the mirror. (Use any variable or symbol stated above

You can view more similar questions or ask a new question.