Algebra Kaplan

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Algebra Kaplan

by resilient » Sat Apr 05, 2008 5:42 pm
What is the greatest possible value of d if
d=12-(c+4)^2

a.-4
b.0
c.8
d.12
e.28



qa is d because (c+4)^2 is always positive and the d can only be 12 at the most. This is the logical answer that comes from the back of the book. However, is there another way to answer this? I tried backsolving and this really is not a good question to do that with.
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by mmukher » Sat Apr 05, 2008 8:57 pm
The method that you described is probably the fastest way to solve this one. I did it the same way as well.

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hmm

by resilient » Sat Apr 05, 2008 10:27 pm
is there a way to step back and plug numbers. I feel as if there are other easier way to do this!
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by AleksandrM » Tue Apr 08, 2008 11:01 am
what if you forget about the 12 and just focus on the (c + 4)^2. If you solve this expression, then you see that c = -4. which means that the expression is (-4 + 4)^2, which is 0. So d must be 12. Am I right?

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by cjiang16 » Wed Apr 09, 2008 4:27 pm
When C=-4, the value of d is 12.