Results 1 to 2 of 2

Math Help - Transformations

  1. #1
    Newbie
    Joined
    May 2010
    Posts
    5

    Transformations

    I need some help with these questions. It's asking me to find the image of the line with the equations y=2x-3 under each of these instances:

    a) a rotation of 90 degrees about the origin.
    b) a reflection in the y-axis
    c) a translation of 2 units parallel to the x-axis in positive direction.

    a) is x=2y-3? I basically guessed this answer, but i'm not sure WHY it is this answer lol.
    b) y=-2x+3?
    c) i know that the line crosses through point (3/2,-3) does this mean i move this point by 2 x units and substitute this into y=mx+c equation?

    Cheers
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor
    Joined
    Aug 2007
    From
    USA
    Posts
    3,111
    Thanks
    2
    #1) You must think about what you are doing. There never has been, and never will be, a "lol" theorem.

    You have y = 2x-3

    a) 90 rotation about the origin. Think on its properties.

    Is there a point that will be on both lines?
    Is there a predictable point? How about (0,-3). Where will that go?
    Is it acceptable to leave it solved for x, rather than for y?

    b) Reflection on y-axis. This is the easiest, I think. Simply substitute -x for x. Done.

    c) 2 to the right. This one is almost as easy as b).

    The slope will not change.
    Where will (0,-3) go? (2,-3)? You're almost done.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Transformations
    Posted in the Pre-Calculus Forum
    Replies: 1
    Last Post: May 9th 2010, 06:21 PM
  2. Transformations of e^x and lnx
    Posted in the Pre-Calculus Forum
    Replies: 3
    Last Post: March 16th 2010, 05:42 PM
  3. Transformations
    Posted in the Calculus Forum
    Replies: 4
    Last Post: April 18th 2009, 10:47 AM
  4. transformations
    Posted in the Advanced Algebra Forum
    Replies: 0
    Last Post: December 1st 2008, 10:17 AM
  5. f(x) transformations
    Posted in the Pre-Calculus Forum
    Replies: 4
    Last Post: April 11th 2008, 12:46 PM

Search Tags


/mathhelpforum @mathhelpforum