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thread: Help with Maths question

  1. #19
    Registered User

    Aug 2007
    3,526

    the only formulas i have been given is the one i mentioned up above - and
    A=s(s-a)(s-b)(s-c) all under that square root symbol
    and s=a+b+c
    2


    thats divided by 2

  2. #20
    Registered User

    Dec 2005
    6,706

    That's Heron's formula that I mentioned.

    It's a funny question, as the only ways I can find to get the perpendicular height require you to first get the area (either from the standard half times base times height formula) or using the uglier heron's formula. You'll get the same answer either way.

    If it's any comfort, I did come across a reference to this exact same problem on a mathematics forum... and they have the exact same solution as I do.

    BW

  3. #21
    Registered User

    Jan 2006
    Melbourne
    2,732

    Wow BG you are doing a great job

    If it helps either of you, my DH recently did his masters in electronic engineering and swears by Wikipedia for help with higher maths problems. Me? I never learnt my times tables so I struggle with the basics

  4. #22
    Registered User

    Aug 2007
    3,526

    BW - so how did u get 4.8 for the perpendicular height? Thanks a bunch also for your help!

    RoryRory - MATHS SUCKS dosent it! LOL - thanks for the advice i will check out wikipedia - WOW on ur husband doing his masters!! he must be a genious!

  5. #23
    Registered User

    Dec 2005
    6,706

    The area of the triangle is 24.

    If you then use the area formula using the side of 10 as the base...

    If A=0.5bh, then if you rearrange the formula

    h=2A/b

    2*24/10 = 4.8

    If you don't like rearranging formulas,

    24=0.5*10*h
    48=10h

    so h = 4.8

    Make sense? I know a lot of people can be really uncomfortable with the algebra you use in rearranging and solving equations, so I've given you two different ways of looking at the same thing.

    BW

  6. #24
    Registered User

    Aug 2007
    3,526

    yay thankyou - yes that does make sense!!! thankyou so very much

  7. #25
    Registered User

    Jul 2006
    Melbourne
    3,715

    OMG, you girls are giving me BAD flashbacks, SOHCAHTOA!!!! I thought I'd permanently blocked all that stuff out. Gosh I hated Maths at school, especially trig, and I don't think that has changed!!! What I'm struggling to believe is that I actually used to be able to do this stuff...........now I wouldn't have a clue

  8. #26
    Registered User

    Dec 2006
    In my own private paradise
    15,272

    Wow BG you are doing a great job
    wow - i didn't even post and i got complimented!!
    i agree BW, you're doing a fantastic job

  9. #27
    Registered User

    Oct 2004
    WA y WA y A WAy
    2,161

    are you doing the tertiary prep program through Usq at all cause i had those exact questions ..

  10. #28
    Registered User

    Aug 2007
    3,526

    LOL BG - ops must of had you on my mind! hahaha

    Sorry BW - thankyou for your help!

  11. #29
    Registered User

    Dec 2005
    6,706

    It wasn't you, hj, it was Roryrory... No worries - we're both used to it by now! And we usually know which one you mean anyway.

    BW

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