Yahoo Answers is shutting down on May 4th, 2021 (Eastern Time) and the Yahoo Answers website is now in read-only mode. There will be no changes to other Yahoo properties or services, or your Yahoo account. You can find more information about the Yahoo Answers shutdown and how to download your data on this help page.

Pope
Lv 7
Pope asked in Science & MathematicsMathematics · 1 decade ago

Locus of solutions to an equation?

Describe in detail the locus of points in the x-y plane satisfying this equation:

(x² + y² - 14x + 8y + 65)(7x² + 16xy - 15y² - 7x + 5y) = 0

3 Answers

Relevance
  • ?
    Lv 7
    1 decade ago
    Favorite Answer

    The first factor appears to be a circle, but completing the square yields:

    (x - 7)^2 + (y + 4)^2 = 0

    The radius is 0, so it is just a point, namely (7, -4).

    The second factor can be factored further to:

    (7x - 5y)(x + 3y - 1)

    Which describes two lines:

    7x - 5y = 0 and x + 3y - 1 = 0

    -5y = -7x and 3y = -x + 1

    y = 7x/5 and y = -x/3 + 1/3

    So the locus is the point (7, -4) and the lines y = 7x/5 and y = -x/3 + 1/3.

  • ?
    Lv 7
    1 decade ago

    [(x -7)^2 + (y +4)^2]*[(x + 3y -1)(7x - 5y]= 0

    first expression is like circle with zero radius

    Is it two intersecting lines ?

    3y = 1 - x

    5y = 7x

    Not too sure

    Wolfram might clarify

    http://www.wolframalpha.com/examples/DifferentialE...

    Regards - Ian

  • ?
    Lv 7
    1 decade ago

    I got two lines that cross near zero. One line goes thru zero with a positive slope and the other is a

    line with negative slope not thru zero but close.

    And then there's a spherical object at (7,-4)

    Source(s): Dreams and loss of sleep
Still have questions? Get your answers by asking now.