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  1. #1
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    geometry help

    In quadrilateral ABCD AB=5, BC =8, and CD = 20 units angle B and C both right angles . what is length of segment AD ?

    answer was 17 units how ? my answer was different how ?


    sri
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  2. #2
    Moo
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    Hello,

    Let E (on [DC]) be the point such as ABCE is a rectangle.
    Its dimensions are 8x20

    So you have DE=DC-EC=20-5=15
    AE=BC=8

    ADE is a rectangle triangle in E, so you can use the Pythagorean theorem and have AD
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  3. #3
    Newbie veronica mars's Avatar
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    what did u get??

    i thought i was doing it right, but i got 20.61552813
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  4. #4
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    Hello, sri340!

    In quadrilateral ABCD\!:\;\;AB=5,\;BC=8,\;CD = 20.
    \angle B \,=\,\angle C \,=\,90^o
    What is length of segment AD ?

    Answer was 17 units.
    My answer was different . . . how ?

    It's hard to see your work from here . . .
    . . But it looks like you played the {\color{blue}J\heartsuit} instead of the {\color{blue}3\clubsuit}
    Code:
                      A   5   B
                      * - - - *
                    * :       |
                  *   :       |
                *     :8      |8
              *       :       |
            *         :       |
        D * - - - - - + - - - * C
          :    15     E   5   :
          : - - - - 20  - - - :

    In right triangle AED, use Pythagorus:

    . . . AD^2 \;=\;DE^2 + AE^2

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