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Math Help - Equations

  1. #1
    Junior Member Soldja Soul3ss's Avatar
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    Equations





    Thanx for the help guys.
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  2. #2
    is up to his old tricks again! Jhevon's Avatar
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    I'm kind of tired, so check my answers with my solutions and make sure i picked the right one

    1)
    Ans: C

    Solution:
    x^2 + 2x - 24 = 0
    => (x + 6)(x - 4) = 0
    => x = -6, x = 4

    2)
    Ans: B

    Solution:
    x^2 + 4x - 3 = 0
    => x = [-4 +/- sqrt(16 + 12)]/2 = -2 +/- sqrt(7)

    3)
    Ans: E

    Solution:
    x^2 - 8x + 5 = 0
    => x = [8 +/- sqrt(64 - 20)]/2 = 4 +/- sqrt(11)

    4)
    Ans: D

    Solution: x = 0 or x - 5 = 0
    => x = 0, x = 5

    5)
    Ans: D

    Solution: x - 2 = 0 or 2x - 5 = 0
    => x = 2, x = 5/2

    6)
    Ans: A

    Solution:
    x^2 + 4x - 21 = 0
    => (x + 7)(x - 3) = 0
    => x + 7 = 0 or x - 3 = 0
    => x = -7, x = 3

    7)
    Ans: B

    Solution:
    x^2 = 196
    => x = +/- sqrt(196) = +/- 14

    8)
    Ans: D

    Solution:
    9 = (n^2 - 3n)/2
    => 18 = n^2 - 3n
    => n^2 - 3n - 18 = 0
    => (n - 6)(n + 3) = 0
    => n = 6, n = -3
    => n = 6, since we can't have -3 sides

    I will do the rest soon
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  3. #3
    Junior Member Soldja Soul3ss's Avatar
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    You live around the same country as me!!! its only around 10, long day or what? lol
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  4. #4
    is up to his old tricks again! Jhevon's Avatar
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    Quote Originally Posted by Soldja Soul3ss View Post
    You live around the same country as me!!! its only around 10, long day or what? lol
    it's been more like a long two days, i slept like 2 hours last night

    9)
    Ans: D

    Solution:
    let the width of the deck be x
    let the area of the deck and pool be A

    then the new length is 40 + 2x
    the new width is 25 + 2x

    => A = 1584 = (40 + 2x)(25 + 2x)
    => 4x^2 + 130x - 584 = 0
    => 2x^2 + 65x - 292 = 0
    => x = [-65 +/- sqrt(65^2 + 4(2)(292))]/4
    => x = 4 .........i only took the positive answer


    10)
    Ans: C

    Solution:

    let the width be x
    then the length is x + 5

    => A = 500 = x(x + 5)
    => x^2 + 5x - 500 = 0
    => x = [-5 +/- sqrt(25 + 2000)]/2 = 20
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  5. #5
    Junior Member Soldja Soul3ss's Avatar
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    It doesnt tell which ones are wrong, it just does it and shows me my score on a different page. Wish i knew also, but as long as i get a 80% or higher i dont have to do 3 more tests. So 9/10 is a blessing from god in my eyes. Unfortunately i have 6 more to do total from being wrong on 2 tests making you guys here a little bit busy ^^, maybe 9 more after i post this next thread in the right place lol. Unless you wanna stay up to help a brotha out rofl. But i suggest you go to sleep .
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  6. #6
    is up to his old tricks again! Jhevon's Avatar
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    all my solutions are correct. i double checked. maybe you clicked the wrong letter or something

    and that's stupid, why wouldn't it tell you which you got wrong. shouldn't a student be able to see where he is weak and thus prepare for tests based on that?
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  7. #7
    Junior Member Soldja Soul3ss's Avatar
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    Well that test is the first assignment of teh lesson, if you dont pass it with 80% or higher you have to do 3 more and there are no practices, just very non detailed lessons on the type of algebra. But i guess its best to just not go on about it off topic kinda, the admin is upset with me already lol.
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