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Math Help - reflection in x=1/2

  1. #1
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    reflection in x=1/2

    If i reflect the point (x,y) in the the line x=1/2

    what will the coordinates of the new point become?
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  2. #2
    A riddle wrapped in an enigma
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    Quote Originally Posted by millwallcrazy View Post
    If i reflect the point (x,y) in the the line x=1/2

    what will the coordinates of the new point become?

    Hi millwallcrazy,

    Where is point (x, y)? Do you want to reflect it across the line x = 1/2 ? Can you be a little more specific?

    x = 1/2 is a vertical line.
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  3. #3
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    Geometrically, to "reflect" a point in a line you draw a perpendicular to the line and find the point on the other side of the line, on that perpendicular, at the same distance from the line. Another way of saying that is that the midpoint of the line segment between the two points is on the given "reflecting" line.

    Since this is x= 1/2 a perpendicular line has constant y. If the given point is (a, b) the reflected point must be of the form (x, b) and we must have (a+x)/2= 1/2. then a+ x= 1 so x= 1- a. The point (a, b) reflects to (1-a, b).
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  4. #4
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    yes its just a general point being reflected in the vertical line x=1/2

    like if you were to reflect the point (x,y) in the vertical line x=0 the new point would be (x,-y)
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  5. #5
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    lol sorry reflecting (x,y) in the vertical line x=0 would give (-x,y)
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  6. #6
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    Quote Originally Posted by millwallcrazy View Post
    If i reflect the point (x,y) in the the line x=1/2

    what will the coordinates of the new point become?
    you cant figure it out without knowing the real coordinates...

    (x,y) being the origin?
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  7. #7
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    Look at my [revious response. (x, y) "reflects" in the line x= 1/2 to (1- x, y).
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