Results 1 to 2 of 2

Math Help - Solve for the Identified Variable

  1. #1
    Newbie
    Joined
    Nov 2008
    Posts
    9

    Solve for the Identified Variable

    a.) A = P+P*r*t for r

    Does anyone else get r = (A/P-1)/t ?

    b.) d = (sqrt(4*R^2-C^2))/2 for C

    Does anyone else get C = sqrt((-2d)^2)/4)+R^2

    c.) 1/f = 1/q+1/p for q

    Does anyone else just get f^-1-p^-1=q^-1?
    Follow Math Help Forum on Facebook and Google+

  2. #2
    A riddle wrapped in an enigma
    masters's Avatar
    Joined
    Jan 2008
    From
    Big Stone Gap, Virginia
    Posts
    2,551
    Thanks
    12
    Awards
    1
    Quote Originally Posted by ZE2001 View Post
    a.) A = P+P*r*t for r

    Does anyone else get r = (A/P-1)/t ?

    b.) d = (sqrt(4*R^2-C^2))/2 for C

    Does anyone else get C = sqrt((-2d)^2)/4)+R^2

    c.) 1/f = 1/q+1/p for q

    Does anyone else just get f^-1-p^-1=q^-1?
    a) Your answer is correct, but I would have done it this way. Less complex:

    A=P+Prt

    A-P=Prt

    r=\frac{A-P}{Pt}

    b) You lost me on this one.

    d=\frac{\sqrt{4R^2-C^2}}{2}

    d^2=\frac{4R^2-C^2}{4}

    4d^2=4R^2-C^2

    4d^2-4R^2=-C^2

    4R^2-4d^2=C^2

    C^2=4R^2-4d^2

    C=\sqrt{4(R^2-d^2)}

    C=2\sqrt{R^2-d^2}

    c) I don't see where you solved for q in your attempt.

    \frac{1}{f}=\frac{1}{q}+\frac{1}{p}

    Multiply through by the LCD of fqp

    qp=fp+fq

    qp-fq=fp

    q(p-f)=fp

    q=\frac{fp}{p-f}
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. How can I have figures identified as tables?
    Posted in the LaTeX Help Forum
    Replies: 0
    Last Post: December 16th 2011, 10:56 AM
  2. Solve for the specified variable?
    Posted in the Algebra Forum
    Replies: 2
    Last Post: March 4th 2011, 10:56 AM
  3. Spectral Plot: A question on identified frequency
    Posted in the Advanced Statistics Forum
    Replies: 1
    Last Post: October 19th 2010, 10:29 AM
  4. Solve for Variable
    Posted in the Algebra Forum
    Replies: 6
    Last Post: May 30th 2009, 06:01 PM
  5. Solve for variable using d=rt ?
    Posted in the Algebra Forum
    Replies: 1
    Last Post: February 2nd 2009, 05:19 PM

Search Tags


/mathhelpforum @mathhelpforum