Anonymous
Anonymous asked in Science & MathematicsMathematics · 1 decade ago

How do you graph this function?

x = y^2 - 4y + 5

Preferably utilizing 'completing the square' method. Thanks.

Also does anyone know an online program/download that can graph functions of the form x = f(y)?

Update:

Also what is the vertex and what are the relevant intercepts.

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  • NEW
    Lv 4
    1 decade ago
    Favorite Answer

    x = y^2 - 4 y + 5

    x= y^2 - 4 y + 2 + 3

    x = ( y - 2 ) ^2 + 3

    Now to graph it let's do the following

    Replace all x's with y's and y's to x's

    y = (x-2)^2 + 3

    Now you can graph each part:

    first you should know how to graph y = x, draw it and consider it fun1

    Then x - 2 means you shift fun 1 to the right by two steps gives u fun2

    Then (x-2)^2 means you multiply each point you got from fun 2 by itself

    which gives you positive points only (above the x axis) .. call it fun3 Shift the entire graph (fun3) up by three steps ... gives you fun4

    Now fun4 is the graph of y = (x-2)^2 + 3

    now to go back to x = y^2 - 4y + 5 you need to do the inverse graph

    Inverse graph is the mirror of the function around angle 45

    In other words, draw a line starting from 0,0 and extend it to make 45 degree with the x- axis and consider it as a mirror to fun 4 , the result will be you final graph for x = y^2 - 4y + 5

    This link about inverse graph http://www.purplemath.com/modules/invrsfcn.htm

    You can also use this link to graph regular functions then you have to inverse it by urself

    http://www.walterzorn.com/grapher/grapher_e.htm

    Sorry I couldn't find any inverse function graph er ;(

  • 1 decade ago

    Imagine that the position of x and y is reversed, graph that and then turn your head 90 degrees. This is the easiest and most succinct way, there's no reason for anything more complicated.

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