09302002, 12:02 PM  #1 
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Bad Case of the Stupids.
Okay, I will never be a teacher. My ability to explain things to others is severely lacking. Taking it one step further I often find myself looking at a math problem and knowing the answer, but having no clue how I arrived at said answer. Hello problem, come on in... see, the problem I face presents itself in the form of a teacher who constantly (and rightfully so) tells me "show more work." Soo.... could someone tell me how I would show work for the following problem (the ^ is used to show powers, x^2 is x to the 2nd). I know about the FOIL method and I truly did arive at the provided answer, its just my head skips steps and assumes things when doing the work. Factor. 12m^2 + 20m +3 The answer is (6m+1)(2m+3) (6m)(2m) + (6m)(3) + (1)(2m) + (1)(3) 12m^2 + 18m + 2m + 3 I just don't know how to properly reperesent the trial and error approach to finding the factors. If you have the time, thanks =) 
09302002, 12:19 PM  #2 
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She probably wants to see that you tried other numbers on paper (instead of in your head) before coming up with the number 6m. Example: 12m^2+20m+3 (3m+3)(4m+1) ... don't work (3m+1)(4m+3) ... don't work blah blah blah...and so on and so forth... (6m+3)(2m+1) ... don't work ...until... (6m+1)(2m+3) AHA! Jackpot! Maybe something like that? I don't know, it's been about 9 years since I took a math class. 
09302002, 12:30 PM  #3 
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She? Did you have a mean female math teacher? =) Yeah.. I thought something like that... guess when you don't know how to show work its hard to know what is going to be acceptable. 
09302002, 12:56 PM  #4 
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I had an algebra teacher who wanted all the work as well. What they are looking for is something like this.. esd.iu5.org/lessonplans/h...Number%201 basically to get the class ready for the quadratic equations and numberline scheme. 
09302002, 01:17 PM  #5 
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UUHHHH....
My cat's breath smells like cat food..... 
09302002, 01:46 PM  #6 
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ok with this problem, there is no need to factor everything before hand. ie 12m^2+30m+3= (6m)(2m)+ (15m)(2)+ (1)(3). You should be able to do that in your head unless the number is a large one. Probably the easiest way to show your work would be to start with the problem and start to reverse foil.ie 12m^2+30m+3= (6m + ?) (2m + ?) Then fill in the ?'s with factors of 3. 3 is prime so there shouldnt be too many =). Then foil that answer to see if its right. If its not, reverse the factors of 3. ie (6m+3)(2m+1)=12m^2+12m+3 (wrong).... and (6m+1)(2m+1) =12m^2+30m+3 yureaka! That should be enough to show your work. I hope that helps. 
10012002, 09:23 AM  #7 
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eronj is on the right track, but he puts the unknowns as the factors of three, which IMHO is wrong because of the reasons he states (three is a prime number). So I would do it this way, using reverse foil. 1. 12m^2+20m+3 From the problem we know that we need to break it down to this initially: (A*m + 1) (B*m + 3). The factors of 3 are {1,3}, and since all signs are positive the signs in the factors also have to be positive. You need to solve for A and B with the factors of 12, which are {1,2,3,4,6,12}. 2. Solve 3*A + B = 20, where A and B are the factors of 12. If A = 12, B = 1, and 3A + B = 36... too much A. If A = 3, B = 4, and 3A + B = 13... too little A. If A = 6, B = 2, and 3A + B = 20... equation works. 3. Plug into result of 1 and get (6m + 1)(2m + 3). There is probably a way to solve for A and B in step two with two equations in two unknowns, but I kept ending up with a squared term, which means you would have to solve for the variables in another quadratic equation, and that didn't make sense to me. Your algebra book probably has a method of solving for the constants. Hope this helps. Its been a while since I had to look at this stuff . 
10012002, 09:39 AM  #8 
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Hmm?
Drop out of college Cendan. You're wasting your time. If the numbers don't pertain to DPS, Flowing Thought, or the AC soft cap, they don't matter. Nekiah Dragonsbane 
10012002, 10:15 AM  #9 
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Re: Hmm?
Nekiah, I am 27 with no degree and no job. For too long I did nothing because I didn't know what to do. Finally I decided that a degree, used or not, is a good start. I figure I will experience things, and even if I don't come out of this knowing what I want to do... I should still come out of it knowing a few things I don't want to do. I know you were being sarcastic.. but I got over the EQ addiction a long time ago. I just use it as something to do while I chat. I would get a lot more done though if friends would log in to ICQ more... then I could do more productive things while I talk. 
10032002, 09:38 PM  #10 
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Re: Hmm?
That's math? Thank god i'm an idiot and therefore am exempt from silliness like that. 
10032002, 10:00 PM  #11 
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.
I love you Cendan! Im your biggest fan! YEAH! Woo! GOOOOOOOOO CENDAN!!!!! YAY!!!!!!!!!!!! 
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