So I fully realize I need to brush up on my Algebra.. but...

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Topic: So I fully realize I need to brush up on my Algebra.. but...
PostTue Apr 10, 2007 6:04 pm
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So im getting the the point where I can set up the problems, but the alebra.. it's been a long time..


how do you solve the following? Does it require FOIL?

14s=6s^2
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Neo2000
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PostSun Apr 15, 2007 12:13 am
All you have to ensure is that you perform the same mathematical operation on both sides to get "s" all by itself and you'll be fine

Divide by s on both sides

14 = 6s

Divide by 6 on both sides
s = 14/6 = 7/3
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PostTue Apr 17, 2007 12:00 am
That is not all you have to ensure, unfortunately. That method will find you ONE factor, but not all of them. If you are ever trying to find factors (or values for a particular variable), do NOT divide out the variable you are supposed to solve for - or you will lose a factor (typically zero).

This is a quadratic so we first to set everything equal to zero:
14s=6s^2
0 = 6s^2 - 14s
then, factor out (NOT divide out) an s
0 = s(6s-14)
now set each factor equal to zero
0 = s
0 = 6s-14 => 14 = 6s => 14/6 = s

So 7/3 is one factor, but 0 is also a factor.
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