Results 1 to 3 of 3

Math Help - Linear simultaneous equations help please D:

  1. #1
    Newbie
    Joined
    Sep 2007
    Posts
    22

    Solved! =D Thankyou! =D

    Heya!

    I need some help solving an equation. =]

    We have to find out what x and y stand for.

    For the last 10 sums, all I had to do was draw a giant sum, and cancel whatever is canceled out and work it out from there. But I can't do it for this one:

    4x + 2y = 20
    3x + 2y = 16

    So what do I do?

    (Also, the teacher said that some of the answers say "No solution". Do you think this a "No solution" answer?)
    Last edited by Hikaru; February 3rd 2008 at 01:29 AM. Reason: Update
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Flow Master
    mr fantastic's Avatar
    Joined
    Dec 2007
    From
    Zeitgeist
    Posts
    16,948
    Thanks
    5
    Quote Originally Posted by Hikaru View Post
    Heya!

    I need some help solving an equation. =]

    We have to find out what x and y stand for.

    For the last 10 sums, all I had to do was draw a giant sum, and cancel whatever is canceled out and work it out from there. But I can't do it for this one:

    4x + 2y = 20 .... (1)

    3x + 2y = 16 .... (2)

    So what do I do?

    (Also, the teacher said that some of the answers say "No solution". Do you think this a "No solution" answer?)
    Mr F edit in red.

    Subtract equation (2) from equation (1): (4x + 2y) - (3x + 2y) = 20 - 16 => x = 4.

    Sub x = 4 into equation (1): 4(4) + 2y = 20 => 16 + 2y = 20 => 2y = 4 => y = 2.
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Newbie
    Joined
    Sep 2007
    Posts
    22
    Quote Originally Posted by mr fantastic View Post
    Mr F edit in red.

    Subtract equation (2) from equation (1): (4x + 2y) - (3x + 2y) = 20 - 16 => x = 4.

    Sub x = 4 into equation (1): 4(4) + 2y = 20 => 16 + 2y = 20 => 2y = 4 => y = 2.
    Ohhhhh coolio. =] Thanks!
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Replies: 3
    Last Post: February 27th 2009, 08:05 PM
  2. Two Simultaneous linear equations
    Posted in the Pre-Calculus Forum
    Replies: 1
    Last Post: December 11th 2008, 11:20 AM
  3. Simultaneous linear equations
    Posted in the Algebra Forum
    Replies: 6
    Last Post: November 17th 2008, 12:58 PM
  4. Simultaneous and linear equations
    Posted in the Algebra Forum
    Replies: 2
    Last Post: February 2nd 2008, 01:49 AM
  5. Simultaneous Linear Equations
    Posted in the Algebra Forum
    Replies: 3
    Last Post: March 11th 2007, 06:32 PM

Search Tags


/mathhelpforum @mathhelpforum