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    (Original post by Qer)
    will upload in a min
    Name:  Capture.PNG
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    need help in last part

    what I am done so far is
    they mention that the area is twice .I 3sqroot3 which becomes 6sqroot3
    then then I use formula
    1/2 (AD)*(SQROOT 24) * Sin30=6sqroot 3
    to find AD length

    then I try to use modulus here
    I set an expression
    as D lies on L

    (..........)^2=AD (ad=6sqroot 2)
    and then take a square to remove sqroot
    and get an equ
    6lenda^2 -24 lenda-19 =0


    (I thought that by doing that I will get two values of lenda and will sub that in
    -1+2lenda
    lenda-4
    6-lenda
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    (Original post by Qer)
    Name:  Capture.PNG
Views: 7
Size:  173.7 KB

    need help in last part

    what I am done so far is
    they mention that the area is twice .I 3sqroot3 which becomes 6sqroot3
    then then I use formula
    1/2 (AD)*(SQROOT 24) * Sin30=6sqroot 3
    to find AD length

    then I try to use modulus here
    I set an expression
    as D lies on L

    (..........)^2=AD (ad=6sqroot 2)
    and then take a square to remove sqroot
    and get an equ
    6lenda^2 -24 lenda-19 =0


    (I thought that by doing that I will get two values of lenda and will sub that in
    -1+2lenda
    lenda-4
    6-lenda
    Could you please upload an image of your working?
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    (Original post by Muttley79)
    Could you please upload an image of your working?
    I don't have my phone with me now(I am in library and forgot mobile at home .I will upload my working when I will go home...)
    thanks for response
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    the height of triangle CDA will be the same as that of triangle CAB.

    it follows that the base of triangle CDA must be double that of triangle CAB.... in other words length AD = 2AB

    suppose AB were 8 units long. then D could be 16 units away from A so that DAB was a line, or 16 units away from A so that ABD was a line.
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    (Original post by the bear)
    the height of triangle CDA will be the same as that of triangle CAB.

    it follows that the base of triangle CDA must be double that of triangle CAB.... in other words length AD = 2AB

    suppose AB were 8 units long. then D could be 16 units away from A so that DAB was a line, or 16 units away from A so that ABD was a line.
    thank you
    Finally got right answer

    so the whole point is if the area gets double it means it base gets double
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    (Original post by Qer)
    thank you
    Finally got right answer

    so the whole point is if the area gets double it means it base gets double
    https://i.imgur.com/XJyemeI.jpg
 
 
 
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