Results 1 to 2 of 2

Math Help - Can you explain to me how to do this?

  1. #1
    Newbie
    Joined
    Jun 2008
    Posts
    1

    Question Can you explain to me how to do this?

    I know that this is fairly simple,
    but I forgot how to do this so could you please help me??
    Are there any specific steps that you have to take??

    7x+2y= -28

    and

    21d*d+85d-26=0

    If you can help me that would be really great.
    Thank you
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Bar0n janvdl's Avatar
    Joined
    Apr 2007
    From
    Meh
    Posts
    1,630
    Thanks
    6
    Quote Originally Posted by sweetcitru View Post
    I know that this is fairly simple,
    but I forgot how to do this so could you please help me??
    Are there any specific steps that you have to take??

    7x+2y= -28

    and

    21d*d+85d-26=0

    If you can help me that would be really great.
    Thank you
    The first one cannot be solved unless you have another expression. It must be solved by simultaneous equations.

    For the second one:

    21d^2 + 85d - 26 = 0

    You'll need to factor out here.

    (3d + 13)(7d - 2) = 0

    Thus:

    3d = -13
    d = \frac{-13}{3}

    OR

    7d = 2
    d = \frac{2}{7}
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Explain this!
    Posted in the Math Challenge Problems Forum
    Replies: 4
    Last Post: December 30th 2010, 02:41 PM
  2. How can i explain???
    Posted in the Number Theory Forum
    Replies: 2
    Last Post: June 6th 2010, 03:37 PM
  3. Can someone explain this to me?
    Posted in the Calculus Forum
    Replies: 1
    Last Post: August 29th 2009, 07:11 AM
  4. Can someone explain how I do this one?
    Posted in the Trigonometry Forum
    Replies: 1
    Last Post: July 15th 2008, 07:22 PM
  5. Can someone explain..
    Posted in the Algebra Forum
    Replies: 6
    Last Post: June 4th 2008, 11:54 AM

Search Tags


/mathhelpforum @mathhelpforum